At
www.ledtronics.com
you can find a reflective vest with LED's in it, powered by two AA batteries. I have one and can testify that it is a nice thing to have in the dark. Mine cost $30 (USD) a couple years ago. The 16 LED's don't do much in near-darkness, but in full darkness they are nice.
If you want to march down the road to dorkiness, it is easy to build a headlight out of PVC pipe and a 20-watt halogen spotlight bulb. I did that, and it is a thing of beauty in terms of brightness, but it won't get any style points. The total cost, including battery and charger, was about $60. I think it compares well, in brightness, with commercial lights in the multi-hundred dollar range. Unfortunately it looks like a piece of two-inch sewer pipe, because it is.