I made a hand cranked flashlight, sort of. I disassembled a defunct NED CD-ROM drive, and used the DC motor and gear assy that opens and closes the door, etc. I sawed off most of the plastic, leaving the motor and five gears. For a crank, I screwed an inch long screw into the cam gear, which when turned slowly, spins the motor fast. I soldered a superbright red LED onto the red and black wires from the motor and taped the LED to the frame (maybe epoxy it later).
Now I can just crank the big cam gear and the motor puts out enough current to light the LED brightly. It takes two hands, so it isn't really practical, but for the first try, it's pretty good.
Earlier, I took the motor by itself from another CD-ROM drive, and soldered a red LED to it. I can spin the shaft and light the LED brightly, but after a few times, the gear teeth make my fingers raw, so it's not really practical. But it's still kind of cool.