Obsequieum is an open source MP3 jukebox for Linux. It's networked which means that it can be used as a radio station or as a music archive. From the web site

"This first version of Obsequieum is basically a multi user streaming jukebox. However, this presents the foundation for more advanced projects such as the globally programmed radio stations with DJs scattered all over the globe. Obseqeieum would also be very useful for office/home environments where people would normally share CDs. A server can be set up to run Obseiqueum and then people contribute music to the server. Beyond this, multiple Obs servers could aggregrate the content transparently to make them seem as one big server, while all the content would transparently be managed between the servers. "