Here’s a cool gadget called HyMini that will wind power to re-charge your gadgets. Although it’s a hefty price to pay at $50, it probably beats building one yourself. (You could make one for about $20 for sure.) They did overprice this thing probably for the design. If they mass-produced it in the near future, it should only cost you around 5 bucks.
If you drive to work on the highway a lot, this might come in handy as you can simply hang it out your window for some nice 80mph wind power.
There’s also an option to use solar power too, which is way too cool.
HYmini is a handheld, universal charger/adapter device that harnesses renewable wind power / solar power and conventional wall plug power to recharge almost all your 5V digital gadgets.