I just bought a couple of those self-charging flashlights (with magnet and coil charging a capacitor). They work ok. I bought them at Wal Mart for 16 bucks. I got a large and a small. I keep one in the truck (large). I keep flashlights in the truck and they are often dead. They both use LED's. The smaller one has to have the button depressed continuosly. I am not sure why they did that.