Here's a (crappy) pic of mine. I had to clamp cardboard over the top to keep him from jumping inside and smacking the wires (I haven't installed the monitor or top glass yet). Obviously, I put the cardboard there for the specific purpose of providing a nice spot for him to recline while he played with my controls. My wife IM'd this to me while I was at work one day - she thought it was hi-larious.
mamecats.com!