I love this thread, probably the most interesting on the forum right now.
I am working on a project as well, although my expertise is not in designing but it brings up important questions. I have dealt with cooling as a hobby for a long time, DI and N2 setups. I am in talks with Spondoolies about getting some chips for a project with a little different concept. I also want to increase headroom by down clocking the chips but in a large format - i am planning on putting emphasis on the cooling aspect to allow the system to be clocked for maximum efficiency.
The reason I am using a large number of chips is to offset the cooling costs.
Couple of pics of Overclocking an old school C2D to over 5000 Mh with a locked multiplier using a little DI

