I've written RadioClouds as a test application for the SoundCloud API. Basically it's a SoundCloud user browser, displaying relations and connections between users. Also it plays their most popular track.
It's an ActionScript 3.0 project, compiled in Flash IDE. It should be also possible to build it with any other AS3 compiler (although the font dependency should be solved accordingly). Feel free to use the source code in whatever way possible. If you have any questions, just send me an email to matas_at_petrikas.de
Available on Github