I finally went through with my idea to make a C library for dealing with RESTful web interfaces. I have called it libunrest, because of their annoying nature. It can already talk to last.fm and discogs.com, and it will work for facebook once I decidee how to implement specifics of signing. I'll have to completely redo signing if I'm going to support oauth, which seems to be even vaguer than the REST interfaces I've already looked at. I've been working on this in hopes of getting rhythmbox to be able to use discogs, and to update the last.fm plugin to use their new, RESTful API. It's also fun to have code hosted online. I like gitorious.