Tomorrow is moving day, and I'm moving to an apartment with FIOS. 25 megabits up and 25 megabits down. Welcome Davey to the 21st Century. Finally. So all of a sudden I'm thinking about what kinds of services I can run out of my apartment with my symmetrical Internet connection.  

That's all well and good, but this is a NYC apartment, so it's small. That led me to this question -- what's the smallest computer you can buy that can run an off-the-shelf OS like Windows, Mac or Linux? And wouldn't it be great if you could buy a small box that had slots, and in each slot you could put a complete computer? The box would take care of power and there would be no ports, except for Ethernet, which would basically be the internal bus protocol for the box. One jack for Internet, one for power, and say up to 15 additional CPUs (the box would come with one CPU on board). Then I could have a small server farm running from a corner of my desk in my crowded Manhattan apartment with great Internet access. 

Think of it as a fractional horsepower server rack... 

I know I'm dreaming. No such thing exists. But what if!