Princeton Tec's Corona Bike light is perfect if you're a multi-modal type of rider. The water-resistant Corona gives you 12 different modes so you can tailor your light and burn time. Riding to the trail at dusk? Use 1 LED in flashing mode. Hit the trail and crank it up and use all 8 Ultrabright LEDs and see everything. The wide beam pattern floods your entire field of vision with an even distribution of light, eliminating the need for your eyes to adjust quickly from very bright to dark areas. The light is fully regulated, meaning there's no dimming, it's full on until it's off. Though with run times up to a whopping 160 hours, you don't have to worry so much about that. It also comes with 8 AA batteries and both helmet and handlebar mounts.
Batteries: 8 AA Alkaline included (also compatible with Lithium batteries)
Weight: 382 grams w/batteries