The best? Get a squirrel cage fan (the fans that are used in ventilation systems), hook up a couple bendable hoses to it. Make a shroud for your heatsink (or get a really good heatsink to use), then use the squirrel cage fan to cool your computer. I have a squirrel cage fan with 3 outputs, so one is going to my overclocking GF2 GTS, one is going to my CPU (the biggest one), and one is cooling down my hard drives.