Not just folding, anything CUDA.
CUDA doesnt require SLI/Crossfire...the gpu's work independent of each other, side by side actually.
So any board with 4 pci-e slots double spaced can run those.
Also, id like to note that this is a Phenom powered rig, and it was much cheaper to go the AMD route. I was suprised myself, thought it would have been Intel.
Yeah, it gets very hot which is why they used such a large tower and keep the side panel off.