I ordered a 60mm, 90mm, and a 120mm fan from Newegg last night. I am now that much closer to having a torrent box. The computer is going to be my old desktop which I wanted to use as a server, but never got around to finishing it. I need to mod the front of the case for 120mm fan, but the rest of the fans shouldn't require any modding of the case. I may end up changing out the power supply in it with another PSU I have, only if the other one is quieter.

As you can tell I'm going for a quiet box so hopefully it won't bother me when I try to sleep. Currently that computer sounds like a jet taking off.

I'm replacing the 80mm intake with a 120mm, the 80mm exhaust with the 90mm, and the 50mm heat-sink fan with the 60mm. You will not believe how the fan is attached to the heat sink. Basically it just has two long screws screwing into the fins.