This gadget is kind of cool (in a geeky sort of way):

The Forever Flashlight uses no batteries or bulbs. Instead it uses Faraday’s Principle of Induction and a bright LED to produce light without batteries. The light is shaken for about 30 seconds to recharge a capacitor and it will then provide about 5 minutes of light. As the light is shaken, a magnet passes through a metal coil generating electricity. During prolonged use it can be shaken for 10-15 seconds every 2 or 3 minutes.

It seems a bit expensive, but the idea is sound (although I wonder how bright it actually is).

I always carry a flashlight with me and I have a couple in the truck and at home.  You never know when you’ll need one.