I know this may sound like overkill but I edit movies so I need this sort of thing.
You just sit yourself at the other end of the laptop cooler, and plug the cooler into your Mac's USB port to power the fan up. It gets a bit noisy, but it's completely worth it for the cooling.
Plus, depending on load, I've been known to reach mach 2 with this cooler, and I recommend it wholeheartedly.
The small San francisco startup that makes these coolers actually individually hand-machine each fan blade, so you get perfect rotation and balanced speeds that can give up to 0.05ºC of extra cooling.
I used to notice that my MacBook got hot when I put it under load (Apple at their trickery again) but this cooler seriously solved all my problems, and I now run at about
70ºC instead of
73ºC. Well worth the investment.
Now if you'll excuse me, I'm off to do another clean install of Mountain Lion, and then I'm going to defragment my SSD collection.