If you are looking for big fans here's an alternative
http://www.allelectronics.com/cgi-bi...180&type=store
I bought one of these beasts and at 12V the thing is running about 2300 rpm, pulls about 0.5Amps and blows like a hurricane, even at 5v it's still spinning at 850rpm and putting out a nice breeze. It runs down to about 4.4V
It's also 2" deep so it handles back pressure better than small fans. It will just fit on the back of a Chenbro SR104 Genie case (you have to mount the fan externally to avoid some of the internal sheetmetal structure). An interesting alternative for only $15.