Yeah, I'm keeping an eye on Indigo, updates look promising. I might be getting an old Dell Precision Workstation 530 MT that I'll use as a spare machine to solely do renders.
It only has one Xeon CPU (1.7 GHz) ATM, space for another, however I think it'll be quite difficult to source a CPU to fill the second ATM, not to mention some RDRAM (Rambus rimms) as it only has 512MB.