Antec Super LanBoy has 2x 120mm fans which are pretty quiet. Case is easy to work on but is a smaller size - suitable for carrying to Lan parties
Antec SLK3000B is a lot cheaper than the Super LanBoy. The front plastic door is pretty flimsy but on the other hand if its a cruncher you won't be opening it often! Comes with 1x 120mm fan at the rear and has room for 1 on the front with an included dust filter already mounted. The design flaw is that they have a gap under the front housing that allows air to bypass the filer - you just clog it up with tape to force the air to flow via the filter. It has a air duct on the LHS to allow ambient air to be directed on the CPU hsf. However, it doesn't align with my Gigabyte 965P-DQ6 motherboard and e4300 hsf. Case size is bigger than Super LanBoy but smaller than a full tower.
Antec P160WF is probably my favourite. I have a CoolerMaster MiniAquagate R120 watercooler mounted inside this case and it vents via the rear 120mm fan. This keeps my Opteron 165 under control. I dislike the ultra bright blue LED on the front but that doesn't matter now because I have the case turned around so I can access the rear ports.
I considered the Antec 900 case but as it has open mesh grills (to allow superior cooling) it also allows the fan noise to escape. I have most of my cases off the floor so they are too close to face height to put up with noisy fans all day and night. The 900 allows multiple fans including a 200mm whopper on the top so it should cool pretty well.
Doomeva wants one of them for his next rig so I'll probably get my arm twisted into buying one eventually. Its probably the "wow" factor of such a cool looking case that appeals to a 15 yr old boy.