cpu: e6600 or higher
mobo: some fancy asus core2duo mobo
ram: 2gbs of corsair pc2 6400 w/ tight timings.. (or even mushkin.. i believe they have even tigher timings..)
gpu: i'd get 2 x1950xtx's in crossfire. you would get more performance from two 7950gx2's in quad sli, but with the 1950's you get nicer lookin picture, and the ability to run HDR and other eye candy stuff AT THE SAME TIME. and with 2 of those, you'd be hard pressed to find a game that WON'T allow you to do that.
HDDs: 2 raptors in raid 0, two 320gbs or w/e for storage..
PSU: either the ocz 700watt gamextreme, or a pc power and cooling 1k watt or something..
case: something big!
monitor: something BIG.. and cleeeaarrrr!!! 22inch minimum.
what i miss? i could go through and show you the actual parts... but....
"Is virtue a thing remote? I wish to be virtuous, and lo! Virtue is at hand." -Confucius