I have an old hand-me-down shuttle that's a number of years old and works quite well
for audio. Old athlon64 single core running at 2gigahertz with 2 gig ram installed. It
works well with audiophile and delta1010 pci cards. The only problem I had with it was
keeping it clean of dust, which would clog the radiator in back.
I've walked past the newer shuttles in fry's a few times and wished I had the
money to burn on another one one of them. They seem very functional, small, light weight,
and easy to carry around. Because they are small, they are not very expandable.