ProgrammableWeb keeps you up to date with APIs, mashups and the Web as platform. It’s a directory, a news source, a reference guide and a community.

The database of over 900 open web APIs and thousands of applications people have built with them is the most comprehensive resource of its kind. Indexed, cross-referenced, and up-to-date.

ProgrammableWeb also gives you the resources to learn how to use APIs and build applications. Get your hands dirty creating anything from weekend project mashups to enterprise apps to VC-funded companies.

Source: http://www.programmableweb.com/