GoogleBooks is a Ruby wrapper that queries the Google API to search for publications in the Google Books repository. It is authored by Zean Tsoi and provides additional methods and search options. Queries return results, each with their own set of attributes that can be individually configured.
Earlier this year, ProgrammableWeb reported that the New York Public Library (NYPL) had launched the What's on the Menu API, the first public API released by the institution. The New York Public Library has just announced the launch of the NYPL Digital Collections API which allows developers programmatic access to the Library's vast collections of digitized creative works including manuscripts, historical maps, rare prints, photographs and much more.
What could you do if you were spidering two billion web pages per day? Whatever your answer is to that hypothetical, you might as well do it now. The 80legs platform lets you write your own web crawler and sell your apps to users (our 80legs API profile). And if you can build it fast, there's an 80legs contest looking for your entry.