computer exhaust fan

I am setting up a little closet grow and was wondering what the best way to set up a computer fan as an exhaust fan would be? any body have any suggestions?

What i did was buy a laptop charger on ebay for like 8 bucks shipped cut the end off strip the wires then stip the computer fan wires. I did it in the middle of the fan so i can connect more than one with the connectors still attached to the fan

if you wire the fan to a universal power adapter that has a wide range of input volts, you can vary the speed. I used the one where you change the head with two prongs, to fit the back of a cd player or whatever, you can vary the speed of the fan by changing the input, like 5v, 7v 9v 12v or whatever, it makes it a bit more variable cause if its hot I can turn up the amps to the fan and it goes faster.