Anyone who would like to play with this kind of tech should have a look at SoftTH, all you need is 3 monitors and 2 pcie vid cards. Works nicely in some cases and is a lot cheaper than hardware solutions http://www.kegetys.net/SoftTH/
If you click on the above link, one of the search results is this very page! Bizarre portal action? I almost feel if i looked at my puter, i could see the back of my own head!
Damnit Jim, i'm a doctor, not an engineer!