What api's can ruby on rails use?

Im trying to find out all the api's ruby can use so far i've found

Flickr api Amazon api Google maps api yahoo api youtube api rFaceboook api

Does anyone know any others?

There are scads of them. These are pretty broad categories. Amazon has apis for sdb, ecs, and aws, to name three. Google has numerous apis, including calendar, map, search, reader, translate, etc.

But fundamentally, Ruby can access any service. You just have to program it. In many cases someone already has.

Why are you trying to catalog public apis that people are interfacing to using Ruby?