Hi Benjamin,
Sorry to hear about your friends stolen Xbox 360 [:#]
Each Xbox (Classic and 360) does indeed have a MAC address, I can't remember if the shipping box has it referenced. If your room mate uses XBox Live, obviously that will try and sign in, and could potential create an audit trail; and your friend will want his Live account details preserved - so I would give Xbox support a call on:
http://www.xbox.com/en-US/support/contact/Also, bit late now, but Xbox 360's have a Kensington slot on them. Therefore you can use something like this to lock it down to something - click
hereThanks,
Richard
{mcuth: edited to shorten link}