Many of the latest MP3 players, PMP, Mobile phones etc can be charged via a USB port. Did you know you can build a cool Hand crank USB charger made with parts from a Mindstorms kit and Radio Shack. The charger uses a Lego motor to generate current which is passed through a voltage regulator and then to the USB port.
It would make a great stocking stuffer for anyone who uses devices that charge via usb. If you are getting it for a person who likes to build their own things, just collect all the parts put them in a ziplock, and put that in the stocking.
(Video after the jump)

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