Night riding is so much fun. It is important to find a good light that will illuminate the road or trail for you and of course let you be seen. It seems that the best bet if you have the money is to buy a light of at least $150 or more. Light N Motion seems to have good stuff that is what my buddies and I use. They have a light that looks like a blasted freight train coming down the trail and lights a few hundred yards ahead of you in a blue light (about $300 I think). Although this can cause problems with blinding oncoming traffic. Also you need lights on the back of your bike to be seen by others from behind, like traffic and other cyclists. Also remember to go slower then you would during the day at night as you cannot see as well with most lighting systems as in daylight. Also it is best to get a lighting system that is rechargable and not battery powered may be a little heavier and expensive but it will save you on batteries in the long run. It seems that most lights have a run time between 2 and 5 hours depending on brand and light settings.

Once you start riding like this you'll likely be hooked, it is a lot of fun.