Green data center using BeagleBoard

I've gotten the green light to take our department data center green
using the BeagleBoard/Bone. We have a series of web servers for
students in our various classes and rather than set them up on rack
mount servers or even small desktops we are going to run these servers
on a small network of BeagleBoards. I'm hoping to mount the whole
data center on a sheet of plywood and hang it on the wall, perhaps
with a nice Lexan top. I think the power usage of the whole network
will be less than one typical server.