Linux Boxen with Small Footprint?

st. augustine asks this question which I'm sure many of you still in dorms might find useful: "I'm going to be moving into a very small dorm room in a few months and every square inch of space is going to be at a premium. I'd like a small Linux box and I want decent price/performance -- a year or two ago a Cobalt Qube or Corel Rebel.com Netwinder looked okay, but paying $1000 for one of these puppies just doesn't seem reasonable when you can get an AMD box that's twice as fast for $400. Only problem is that the AMD box is the size of a refrigerator, and I'm going to need that space for a refrigerator. Any suggestions?" Ah, yes, I remember the days of living in closets dorm rooms. Does anyone have any pointers?