GNUMP3d

GNUMP3d is a streaming server for MP3s, OGG vorbis files, movies and other media formats.

http://www.gnu.org/software/gnump3d/index.html

To add a stream:

NAME: Any Name 
URL: http://ip:port/search?q=mozart&play=1
TYPE: M3U

Note: the play=1 is the important missing piece that i couldn't figure out. If you have any updates on howto configure stuff like random or anything else, please add... In the example above, it will query (q=text) for mozart and return a playlist in the m3u format which will allow the chumby to play it.