Minecraft music? Yes( send the audioto everyones location ) Your own/custom music? Yes, but you will probarly need a modifyd client to recive the stream, Or that can read "MusicPack"( name got by texurepack ).. That would be usefull
I typt modifyd cuz i am dutch do don't know how to write; modify... And then history of that.. But anyway. Search on plugins.bukkit.org for music or stream or anything like that, cuz i thought there was something just like that