Everything a bike commuter could ask for: A powerful light system with safety side lighting and environmentally-friendly USB rechargeable Li-ion battery.
If you use a computer at work during the day, you can charge this up during the day for your ride home. (It's like getting your boss to buy your batteries. Shhh...)
The optional Light and Motion USB Charger allows you to recharge from an AC outlet.
Save money when you buy this headlight packaged with a tail light:
Light and Motion Urban 550 / Vis 180 Micro Light Set ($179.99)