With irmp3 you can control mpg321 (currently, other players are planned) to play songs, lists, and lists of play lists. irmp3 features 'environments' that you can set to play a certain type of music, alarms, can be controlled over the network, via remote control (requires lirc) and a number of other useful features, including lcd display and keypad input support via lcdproc. it is most useful for those building mp3 jukeboxes with remote controls.