I would also recommend the type of CREE lights linked to above, and would also suggest you can look into CREE flashlights with comparable brightness and attach it to your handlebars with two interlocked hose clamps; or get a cheap flashlight/handlebar mount for a buck or two from dealextreme (many people seem to like the twofish lockblock or its knockoffs). I'm just sayin, you might get a little more bang for your buck if you expand your search to general flashlights, rather than specific bicycle lights.

A word of warning; any super-cheap CREE light packages you are likely to find online has a risk of including bad batteries. I am very happy with a flashlight I bought off eBay for I think $27, but a "full charge" of the two 18650 batteries lasts not much longer than half an hour. (That's the bad news. The good news is that the length of my commute is not much longer than half an hour -- and by the time I get near work, the sun is well up and I can switch to energy-saving blinky mode)

So you might buy a light now, and save up to later spend $20-30 for high quality replacement batteries from an American company (batteryjunction.com, there are others as well). You can read more about batteries in this thread. Good luck!