A través de Digg me encuentro con un completo listado de APIs Web 2.0, seguro que os resultará muy útil, lo reproduzco aquí: ## Advertising [Google AdSense](http://code.google.com/apis/adsense/) Administración de publicidad con Adsense [Google AdWords](http://www.google.com/apis/adwords/) Anunciarse en buscador Google [Microsoft adCenter](http://msdn2.microsoft.com/en-us/library/aa983013.aspx) Servicios de publicidad online de Microsoft UrlTrends Optimización de búsqueda y seguimiento de enlaces Wordtracker Search engine optimization services Yahoo Ads Administración de anuncios online de Yahoo Yahoo Search Marketing Plataforma de publicidad en búsquedas [Answerbag](http://www.answerbag.com/docs/xmlschema/) Questions and answers service Blogwise Blog and feed search service SplogSpot Database of spam blogs ## Blog Search Blogwise Servicio de búsqueda en blogs y feeds SplogSpot Base de datos de blogs de spam Tailrank Blog search and news aggregation service Technorati Servicio de búsqueda en blogs ## Blogging [Akismet](http://akismet.com/development/api/) Servicio de prevención de spam en blogs [Blogger](http://code.google.com/apis/gdata/blogger.html) Servicios para Bloggear [FeedBlitz](http://feedblitz.blogspot.com/2006/10/feedblitz-api.html) Servicio de email para blogs [FeedBurner](http://www.feedburner.com/fb/a/developers) Blog promotion tracking service [LiveJournal](http://www.livejournal.com/developer/) Blogging software Performancing Blog management [TypePad](http://www.sixapart.com/pronet/docs/typepad_atom_api) Blog management Weblogs Blog ping service [Windows Live Spaces](http://dev.live.com/spaces/) Servicios Blogs ## Bookmarks Blogmarks Social bookmarking [del.icio.us](http://del.icio.us/doc/api) Social bookmarking [linkaGoGo](http://www.linkagogo.com/rest_api.html) Social bookmarking service [Ma.gnolia](http://ma.gnolia.com/support/api) Social bookmarking service OnlyWire Social bookmarklet service Shadows Social bookmarking and community Simpy Social bookmarking ## Calendar [30 Boxes](http://30boxes.com/api/) Servicio de Calendario [Google Calendar](http://code.google.com/apis/gdata/calendar.html) Servicio de Calendario Spongecell Servicio de Calendario online ## Chat [AOL Instant Messenger](http://developer.aim.com/plugin) Servicio de mensajería instantánea [AOL Presence](http://developer.aim.com/presenceMain.jsp) Online presence service [Google Talk](http://www.google.com/talk/developer.html) Aplicación de Chat IMified Instant messenger buddy Lingr Online chatroom services [MSN Messenger](http://dev.live.com/messenger/) Chat y mensajería [WebAIM](http://developer.aim.com/webaim/) Web based instant messaging Yahoo Messenger Mensajería instantánea ## Community [Blue Dot](http://bluedot.us/Developers.aspx) Content sharing community coRank Distributed user reviews service [Facebook](http://developers.facebook.com/) Social networking service [PartySpark](http://www.strikeiron.com/ProductDetail.aspx?p=240) Social events service RockYou Super Wall Content sharing platform within Facebook Twitter Community site ## Email [Email Address Validator](http://www.strikeiron.com/ProductDetail.aspx?p=167) Email address validation service ExactTarget Email delivery services [IntelliContact](http://app.intellicontact.com/icp/pub/api/doc/api.html) Email marketing service JangoMail Bulk email service [Mailbuild](http://www.mailbuild.com/api/) Email forms and templates service Publicaster Email marketing management [StrikeIron Email Verification](http://www.strikeiron.com/ProductDetail.aspx?p=179) Email verification service [Vertical Response](http://www.verticalresponse.com/labs/developers/) Email management services Webmail.us Email hosting service [WhatCounts](http://www.whatcounts.com/technology/apis.html) Email management services [Yahoo Mail](http://developer.yahoo.com/mail/) Web based email system ## Enterprise Employease On-demand human resource management [Google Provisioning](http://code.google.com/apis/apps/gdata_provisioning_api_v2.0_reference.html) User provisioning for Google Applications [Lokad](http://www.lokad.com/Support.ashx) Time series forecaster [NetDocuments](http://www.netdocuments.com/Alliances.aspx) Enterprise document management service [NetSuite](http://www.netsuite.com/portal/developers/main.shtml) Business application suite [Salesforce.com](http://www.sforce.com/) CRM services [WebEx](http://www.webex.com/partners/developer-overview.html) Conferencing and collaboration services ## Events Eventfinder Calendario de Eventos [Eventful](http://api.eventful.com/) Events discovery and demand [Spraci](http://www.spraci.com/api/) Events and clubs database [Upcoming.org](http://upcoming.yahoo.com/services/api/) Collaborative event calendar Zvents Local events search and community ## Financial [Blinksale](http://www.blinksale.com/api) Online invoicing services [Currency Rates](http://www.strikeiron.com/ProductDetail.aspx?p=227) Ratios de conversión entre monedas [Dun and Bradstreet Credit Check](http://www.strikeiron.com/ProductDetail.aspx?p=223) Credit check [FreshBooks](http://developers.freshbooks.com/) Online invoicing and time tracking KashFlow Online accounting software [Moneytrackin](http://www.moneytrackin.com/help/API/) Expense tracking NetAccounts Online accounting service [Prosper](http://www.prosper.com/tools/API.aspx) Peer-to-peer network [StrikeIron Historical Stock Quotes](http://www.strikeiron.com/ProductDetail.aspx?p=113) Stock price quotes for US equities [StrikeIron Mutual Funds](http://www.strikeiron.com/ProductDetail.aspx?p=124) Historical mutual funds [StrikeIron Stock Quotes Basic](http://www.strikeiron.com/ProductDetail.aspx?p=115) Real-time stock quotes Wesabe Personal finance management and community ## Government Cicero Lookup service for US elected officials by address [Civic Footprint](http://www.civicfootprint.org/about/api) Political geography lookup for Illinois Democracy In Action Advocacy services for nonprofits [FedSpending.org](http://www.fedspending.org/apidoc.php) Database of US government spending Follow The Money Database of US campaign contributions [GovTracker](http://www.state.ri.us/govtracker/services/) Rhode Island state data services LOUIS US federal documents database Open Patent Services European Patent Office web services [Sunlight Labs](http://sunlightlabs.com/api/) US Congress database service [TheyWorkForYou](http://www.theyworkforyou.com/api/) Track the UK Parliament [Who is my Representative](http://whoismyrepresentative.com/) Database of US congressional representatives ## Internet [Alexa Site Thumbnail](http://aws.amazon.com/ast) Thumbnail images of web site home pages [Alexa Top Sites](http://aws.amazon.com/alexatopsites) Web site traffic rankings [Amazon EC2](http://www.amazon.com/b/ref=sc_fe_l_2/104-7185354-2899168?ie=UTF8&node=201590011&no=3435361) Elastic Compute Cloud virtual hosting [Clicky](http://getclicky.com/help/api) Servicio de estadísticas para sitios web [Compete](http://developer.compete.com/) Internet web site metrics and analytics Cordurl Geo coordinate translation Dapper Service for API creation Domain Tools Internet domain name lookup [Durl.us](http://durl.us/) URL shortening Ecommstats Web analytics [Hostip.info](http://www.hostip.info/use.html) IP lookup [HTML2PDF](http://www.html2pdf.biz/api.php) HTML to PDF conversion [Internet Archive](http://www.archive.org/help/contrib-advanced.php) Non-profit Internet library [IP Address Lookup](http://www.strikeiron.com/ProductDetail.aspx?p=149) Determine IP address from domain name [Mint](http://www.shauninman.com/plete/2005/10/mint-intro-to-pepper-development) Web site metrics and reporting Mon.itor.us Web site monitoring services [MyNotify](http://mynotify.com/info/developers) Feed publication [Nenest](http://www.nenest.com/_doc/Api.aspx) Web forms and application framework [Outune](http://www.outune.com/?ln=mc) Web map engine Pingdom Web site monitoring and reporting [Qurl](http://qurl.com/help_automate.php) Redirección de URL SoftLayer Systems management and monitoring UnAPI Proposal for web clipboard W3Counter Web site metrics tools Webride Attaches discussions to any site WebThumb Thumbnail image generation [Windows Live Custom Domains](http://msdn2.microsoft.com/en-us/library/bb259721.aspx) Web site administration [Yahoo Site Explorer](http://developer.yahoo.com/search/siteexplorer/) Web site analysis service ## Job Search Indeed Job search services SmashFly Job board posting service ## Mapping [ArcWeb](http://www.esri.com/software/arcwebservices/index.html) Mapping and GIS services BigTribe Location based advertising [deCarta](http://www.telcontar.com/products/dds/dds_webservicesapi.html) Location-based services EarthTools Web services for geographical information FeedMap Blog geo-coding Garmin MotionBased GPS services and mapping geocoder Geocoding services for US [geocoder.ca](http://geocoder.ca/?api=1) Geocoding services for Canada [GeoIQ](http://www.geoiq.com/) Geospatial analysis and heat mapping service [GeoNames](http://www.geonames.org/export/) Geographic name and postal code lookup GetMapping Aerial photography and mapping service GlobeXplorer Mapping services Google Maps Mapping services HopStop Mass transit and walking directions [iShareMaps On Demand](http://www.isharemaps.com/products/isharemaps_on_demand/isharemaps_on_demand.html) UK Postcode Geocoder [Map24 AJAX API](http://devnet.map24.com/index.php) Mapping services Mappr Photo mapping MapQuest Online mapping service [Mapstraction](http://www.mapstraction.com/) Mapping API abstraction layer MetaCarta Location and geotagging services [Microsoft MapPoint](http://msdn.microsoft.com/mappoint/) Mapping services [Microsoft Virtual Earth](http://dev.live.com/virtualearth) Mapping services [Multimap](http://www.multimap.com/share/documentation/api/) Global online mapping service NASA Satellite mapping images Naver Maps Korean mapping service [Nearby.org.uk](http://www.nearby.org.uk/api/convert-help.php) Geocoding service for UK Ontok Geocode any US address [OpenLayers](http://www.openlayers.org/) Mapping API abstraction layer [OpenStreetMap](http://wiki.openstreetmap.org/index.php/OSM_Protocol_Stack) The Free Wiki World Map Platial Collaborative geographic service Plazes Location discovery service Poly9 FreeEarth 3D mapping service Pushpin Mapping service Urban Mapping Urban geo-spatial data services USGS Elevation Query Service Determine elevation based on latitude and longitude [ViaMichelin](http://dev.viamichelin.com/) Mapping, directions, and travel booking Wayfaring Map creation and sharing service WHERE GPS Mobile GPS widget platform Where Is Tim Web Service Location tracking Where2GetIt Geospatial Non-mapping geospatial services Where2GetIt SlippyMap Online mapping service Whereis Australian and New Zealand mapping service [Wigle](http://wigle.net/wiki/index.cgi?API) Wireless network mapping Yahoo Geocoding Geocoding services [Yahoo Map Image](http://developer.yahoo.com/maps/rest/V1/mapImage.html) Map image creation service [Yahoo Maps](http://developer.yahoo.com/maps/) Mapping services ZeeMaps Embedded maps and international geocoding ZoomIn Australian mapping service ## Media Management BBC Multimedia archive database [Grouper Video](http://grouper.com/api/) Video sharing service Orb Digital media remote access and management Phanfare Photo and video sharing service Streamload Online media storage ## Medical [cPath](http://www.ncbi.nlm.nih.gov/entrez/query/static/esoap_help.html) Medical database lookup Kegg Bioinformatics data services [NCBI Entrez](http://www.ncbi.nlm.nih.gov/entrez/query/static/esoap_help.html) Life sciences search services [SeqHound](http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=12401134) Bioinformatics research database ## Messaging [411Sync](http://www.411sync.com/cgi-bin/developer.cgi) SMS, WAP, and email messaging Aql SMS solutions portal [Clickatell](http://www.clickatell.com/brochure/products/api_http.php) SMS Messaging services Jaiku Social messaging service Mobivity SMS marketing messaging service [Movil](http://www.movil.be/?s=developer_zone) SMS messaging PartySync Messaging services Sabifoo IM to RSS conversion service [SmsBug](http://www.smsbug.com/api/webservice.asmx) SMS messaging services StrikeIron Global SMS Pro SMS messaging services [StrikeIron Mobile Email](http://www.strikeiron.com/ProductDetail.aspx?p=162) Mobile email messaging service Textamerica Moblogs [Trekmail](http://w2.trekmail.com/stories/storyReader$46) Messaging services Twittervision Location based data for the Twitter service [Userplane](http://dev.aol.com/userplane/index.html) Communication software for online communities Vazu SMS messaging service ## Music AOL Music Now Music playlist management Digital Podcast Podcast search Faces.com Photo and media sharing service Feedcache Feed caching service Freedb / CDDB Online CD catalog service [Last.fm](http://www.audioscrobbler.net/data/webservices/) Music playlist management [MP3Tunes](http://www.mp3tunes.com/api/) Music services [MusicBrainz](http://wiki.musicbrainz.org/XMLWebService) Music metadata community service MusicDNS.org Music fingerprinting service [MusicMobs](http://mobdev.pbwiki.com/) Social music service [OpenStrands](http://www.musicstrands.com/openstrands/overview.vm) Music recommendation and discovery Rhapsody Online music services [SeeqPod](http://www.seeqpod.com/api/) Music recommendation service SNOCAP Digital music marketplace [Soundtoys](http://soundtoys.net/contribute/api) Visual artists works repository [Tunelog](http://tunelog.com/api/) Music metadata management WebJay Music playlist management [Winamp](http://dev.aol.com/winamp/index.html) Customizable music player [Yahoo Music Engine](http://developer.yahoo.com/music/) Desktop music player ## News AmphetaRate News aggregator ClearForest Semantic Web Services1 Natural language processing tools Daylife Online News Service Digg   [Findory](http://www.findory.com/help/api) Personalized news aggregation [Macromedia News Aggregator](http://weblogs.macromedia.com/mxna/Developers.cfm) Data access service Moreover News delivery NewsCloud Social news service NewsIsFree Online news aggregation ## Office [Backpack](http://www.backpackit.com/api/) Online information manager Big Contacts Web based contact management EditGrid Online spreadsheet [Google Documents List](http://code.google.com/apis/documents/overview.html) Document management services Google Spreadsheets Online spreadsheets Numbler Online spreadsheet service [SlideShare](http://www.slideshare.net/developers/) Presentation sharing community Zoho Online office suite ## Photos [AOL Pictures](http://dev.aol.com/aol_pictures) Online photo management Buzznet Photo sharing Flickr Photo sharing service Fotolia Royalty free stock photos [Google Picasa](http://code.google.com/apis/picasaweb/overview.html) Photo management and sharing service [imageLoop](http://www.imageloop.com/de/api/index.htm) Animated slideshow service Panoramio Photo upload site with organizer [Pixagogo](http://www.pixagogo.com/Tools/api/apihelp.aspx) Online photo services Riya Photo search ShutterPoint Stock photography service Smugmug Photo sharing service Snipshot Online photo editing service WebShots Photo sharing service Yahoo Photos Online photo service Zoto Photo sharing service ## Recommendations Criteo Distributed recommendation service [EasyUtil](http://easyutil.com/rec_api_ref.html) Recommendation service RapLeaf Portable ratings system [Yelp](http://www.yelp.com/developers/documentation) Local user reviews and city guides ## Reference [Aonaware Dictionary](http://services.aonaware.com/DictService/) Dictionary lookup service/td> [City and State by Zip Code](http://www.strikeiron.com/ProductDetail.aspx?p=240) Address lookup service [Dun and Bradstreet](http://www.strikeiron.com/ProductDetail.aspx?p=207) Research company background data Bussines Verification Business research services FUTEF Wikipedia API Third party Wikipedia web service ISBNdb Books database [Library of Congress SRW](http://www.loc.gov/standards/sru/) Information database search [Microsoft MSDN](http://services.msdn.microsoft.com/ContentServices/ContentService.asmx) Technical reference library OpenDOAR Academic research repository [PhoneVal](http://www.strikeiron.com/ProductDetail.aspx?p=147) Phone number validation service [RealEDA Reverse Phone Lookup](http://www.strikeiron.com/ProductDetail.aspx?p=157) Lookup address and name via phone SRC Demographics Demographic reference data [StrikeIron Address Verfication](http://www.strikeiron.com/ProductDetail.aspx?p=136) Global address verification service [StrikeIron Do Not Call](http://www.strikeiron.com/ProductDetail.aspx?p=160) Telephone number verification [StrikeIron Insider Trading](http://www.strikeiron.com/ProductDetail.aspx?p=114) Insider trading transaction information [StrikeIron Phone Number Enhancement](http://www.strikeiron.com/ProductDetail.aspx?p=140) Adds address and statistical data based on phone number [StrikeIron Residential Lookup](http://www.strikeiron.com/ProductDetail.aspx?p=233) Residential directory lookup and validation service [StrikeIron Reverse Phone Lookup](http://www.strikeiron.com/ProductDetail.aspx?p=103) Reverse phone lookup services [StrikeIron Sales Tax Basic](http://www.strikeiron.com/ProductDetail.aspx?p=105) Sales and use tax data service [StrikeIron Super Data Pack](http://www.strikeiron.com/ProductDetail.aspx?p=115) APIs for variety of reference data sources [StrikeIron US Census](http://www.strikeiron.com/ProductDetail.aspx?p=134) Census data information service [StrikeIron Zacks Company Profile](http://www.strikeiron.com/ProductDetail.aspx?p=106) Corporate profiles web service Talis Library 2.0 reference services UrbanDictionary Slang dictionary lookup [US Yellow Pages](http://www.strikeiron.com/ProductDetail.aspx?p=213) Telephone directory [Yahoo Answers](http://developer.yahoo.com/answers) Community driven reference service ## Search [Alexa Web Information Service](http://aws.amazon.com/alexawebsearch) Web site information and traffic data [Alexa Web Search](http://aws.amazon.com/alexawebsearch) Web Search Engine Amazon A9 OpenSearch   [Gigablast](http://www.gigablast.com/searchfeed.html)   [Google Ajax Search](http://code.google.com/apis/ajaxsearch/) Web search components [Google Code Search](http://code.google.com/apis/gdata/codesearch.html) Code search service Google Desktop Desktop search and gadgets [Google Search](http://www.google.com/apis/) Search services Kratia Democratic search engine [Naver](http://openapi.naver.com/) Korean search engine Vast Structured web search Windows Live Search Internet search [Wink](http://blog.wink.com/) Social search service [Yahoo Image Search](http://developer.yahoo.com/search/image/V1/imageSearch.html) Image search services [Yahoo Local Search](http://developer.yahoo.com/search/local/V2/localSearch.html) Local search service [Yahoo My Web Search](http://developer.yahoo.com/search/myweb/) Personalized search services [Yahoo Related Suggestions](http://developer.yahoo.com/search/web/V1/relatedSuggestion.html) Search suggestion service [Yahoo Search](http://developer.yahoo.com/) Search services [Yahoo Term Extraction](http://developer.yahoo.com/search/content/V1/termExtraction.html) Contextual search service [AOL Open Auth](http://dev.aol.com/openauth) Authentication services ## Shopping [Amazon eCommerce](http://www.amazon.com/gp/browse.html/ref=sc_fe_l_2/103-1644811-9832630?_encoding=UTF8&node=12738641&no=3435361) Online retailer Amazon Historical Pricing Historical product sales data [Authorize.Net](http://developer.authorize.net/) Internet based payment gateway services [AvantLink](http://www.avantlink.com/api.php) Affiliate marketing network CNET Shopping services [Commission Junction](http://webservices.cj.com/) Online affiliate programs [DataUnison eBay Research](http://www.strikeiron.com/ProductDetail.aspx?p=232) eBay pricing and sales trend data [Direct Textbook](http://www.programmableweb.com/api/direct-textbook) Book price comparison service [eBay](http://developer.ebay.com/) Online auction marketplace GoodStorm Online retail ecommerce [Google Base](http://www.programmableweb.com/api/google-base) Platform for structure and semi-structured data [Google Checkout](http://code.google.com/apis/checkout/) Shopping cart services [PriceRunner](http://www.pricerunner.com/partner/partner.html) Shopping comparison engine [Shopping.com](https://partners.shopping.com/app) Online retail shopping [SwapThing](http://www.swapthing.com/user/wsRegistration.jsp) Community driven swapping site [UPC Database](http://www.upcdatabase.com/xmlrpc.asp) UPC lookup service [Windows Live Expo](http://dev.live.com/expo/) Online classifieds service [Yahoo Shopping](http://developer.yahoo.com/shopping/) Shopping services Zazzle On-demand product creation service ## Storage [Amazon S3](http://www.amazon.com/gp/browse.html/103-7232640-5009469?node=16427261) Online storage services [Box.net](http://enabled.box.net/) Online file storage MoveDigital File delivery and management services Omnidrive Online storage services [Open Xdrive](http://dev.aol.com/xdrive_api) Online data storage service Openomy Online file system Tagalag Email tagging TagFinder Tag extraction service T[agthe.net](http://www.programmableweb.com/api/tagthe.net) Tag recommendation service TagTooga Tag based Internet directory ## Video Truveo Video search Blinkx Video search Dave.TV Video distribution network LiveVideo Video repository and user community Revver Video services Veoh Virtual television and video network Video Detective Film trailers, cast, images, and related information [Yahoo Video Search](http://developer.yahoo.com/search/video/V1/videoSearch.html) Video search [YouTube](http://www.youtube.com/dev) Video sharing and search ## Widgets ClearSpring Widget creation, distribution, and tracking services [Google Gadgets](http://www.google.com/apis/gadgets/index.html)   [Netvibes](http://dev.netvibes.com/) Personalized home page with widgets Pageflakes Personalized start page and widgets [Serence Klip](http://www.klipfolio.com/) Desktop gadgets SpringWidgets Widget platform TagWorld Social web services [Windows Live Gadgets](http://dev.live.com/gadgets/default.aspx?app=gadgets) Online gadgets service Windows Sidebar Gadgets Desktop gadgets [Yahoo Widgets](http://widgets.yahoo.com/workshop/) Desktop widgets [Yourminis](http://www.yourminis.com/developers) Personalized start page ## WIKI DBpedia Interfaz estructurada para solicitudes a Wikipedia JotSpot Utilidad de colaboración con estilo Wiki [PBwiki](http://api.pbwiki.com/) Consumer wiki farm WikiMatrix Servicio de búsquedas y comparaciones en Wiki vía: [Techmagazine](http://techmagazine.ws/full-web-20-api-list/)