I've thought about it. My main problem with the idea right now is that i've got a HUGE collection of .mp3 from when I was a kid, but it was all ripped at 128khz (because I didn't know any better at the time) so it's of little use to me.
I'm also considering just upgrading my PC to vista and then using the xbox360's windows media connection as a means to serve music off of my PC in the office room (for whatever reason, regular windows XP won't talk to the 360, it's gotta be vista or the special XP media center edition)