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http://www.nytimes.com/2006/12/14/te...ref=technology

Article about the DiNotte tail light.

December 14, 2006
This Taillight for Bicycles Leaves Even Some Headlights in Its Wake
By IAN AUSTEN

Bicycle taillights were among the first products in which conventional light bulbs were replaced by light-emitting diodes. The diodes’ relatively low power consumption allowed manufacturers to use smaller and lighter batteries.

At first, L.E.D. taillights suffered from being somewhat dim. But that is not a limitation of the DiNotte Tail Light (www.dinottelighting.com). The lamp, which vaguely resembles a short, fat lipstick tube, holds a three-watt L.E.D., making it more powerful than many bicycle headlights.

On full power, the light projects a large beam of red light well behind the bicycle. The effect is a bit like carrying a red emergency flare.

The light, with a suggested price of $129, uses four AA batteries (rechargeables are recommended), and it runs for 3 hours on high power or 12 hours while blinking or on low, a setting that is still significantly brighter than other taillights. It attaches to any bicycle seat post quickly with an industrial O-ring, while the batteries have a separate case and Velcro attachment.

The aluminum casing is not just for style. The L.E.D.s get hot, so the casing acts as a heat sink to dissipate that energy.