Originally Posted by dustinvallier
Check out the tiny LED lights, like the Photon. Some of them come with clips that you can attach to a hat brim or your watchband or whatever. The batteries last hundreds of hours, and are user-replaceable. Besides, it's cheaper than a cycling light system and makes a good backup anyway.
I've had a white Photon on my keychain for years. While I think they rock,they wouldn't be too useful for what the OP is looking for. The really bright ones(white,blue,turquiose) use 2 batteries and only go for about 10-12hrs. They also don't have enough throw to properly light the ground if you're wearing them on you upper body. Actually,most regular LED's wouldn't work too well when worn on the gead while running. The OP would do better with a LS(Luxeon Star) LED headlamp.
For more info:
http://www.flashlightreviews.com/
http://ledmuseum.home.att.net/