Best for Bike Commuters

NiteRider Mako 150

The 150 lumen light clamps onto a variety of handle bar widths and slides out of its binding quickly for taking with you at your destination. Pressing the glove-friendly button lights up the single LED, sufficiently bright for riding a smooth trail through our local park. Hitting the on button again dims the light to a lower setting and then a strobe. On all, red LEDs blink out of gills on the sides of the light. They're not bright, but from the sides and ahead, you won’t have to worry about being noticed.
[$40; amazon.com]