Think signing petitions is useless? There's probably an app for that. But Change.org proves the cynics wrong--every day. And now there's a Change.org API to rattle the powerful even further. The API is in beta, is free, and uses REST with JSON returned. The API covers a multitude of requests from creating petitions to checking signatures, from looking at the case for a petition to updating them.
How does the Web's largest ticket search engine improve its API? By giving developers easy access to more information, of course. SeatGeek recently made links to artists' Spotify and Last.fm profiles available through the SeatGeek API, and the company promises even more data in the future.