As a follow-up to the original question, how does one have a system
automatically run commands NOT as root when starting up?  Is there
some way (short of writing C, which I could do), to run commands as a
user with fewer privileges?

I have a linux box I'm using as an MP3 jukebox, and I'd be happy to
run some of the housekeeping stuff just as a user in the audio group.

Thanks!
R