cova, i've considered doing that too... but as the rack is going to end up below my desk, it doesn't seem like a good solution to me (air path would be too restricted), nice to see people post their ideas though
I think i'm going with the huge rad idea... still have to figure out where to put it though, and the second problem would be the pump(s)... I have no idea how much pumpin' power i would need (i can cheap & easily get mini/maxi/micro-jets and sicce pumps). Sicce pumps look interesting, problem is that they need to be submerged (don't know if they are easy to mod to inline)