There are tons of lights out there. For basic commuting a 10W halogen is usually enough to be seen by. If you are riding on a dark path it will let you see in a puddle of light. At my age I prefer 20W. I have used primarily NiteHawk commercial lights in the past, reliable and not too expensive. Light & Motion seems to have some well built lights, including some non-HID systems. They run a high price tag but seem to be reliable. NiteRider has the distinction of being the only system I have actually thrown away in disgust. I know there are lots of happy NiteRider customers out there, but I got one of the ones that eats batteries. At a $100 a pop that is no small matter. Neither is having a 3 day old replacement battery fail on your way home on a cold, dark, night. Look at Performance or Nashbar, at this time of year they start having sales on lights. If you are interested in a home brew PM me and I can give you some web-sites to help you get started, it really is not hard. I've been running a home brew system for 2 years now. I like the battery only costing $30-40, and being able to get a replacement bulb locally. By the way, I've never had a problem with water leaks, even in my home brews.