Home Server Rooms?

Tuzanor writes "I've got a buddy moving into a brand new house. Being geeks, we've decided to wire the house with a large home network. While this story took care of wiring the house, we need to figure out how to create a well set up server room. We'll be having both towers and rack mounted computers as well as various switches, UPSes, etc. Also, we figure this room will get warm, even in winter. How may we cool it while still keeping the rest of the house toasty warm on a cold Canadian night (without opening a window)"