Last week we took a look at MightyMintyBoost, a solar-powered USB charger. If you liked the idea but can’t count on the sun shining, this USB charger runs on the power of your bicycle pedals.
Like the solar-powered charger, this pedal-powered charger is based off the previously mentioned MintyBoost charger (which is simply powered by AA batteries). As opposed to the, which is built to be as easy to assemble as possible, the geek quotient that lies within this Instructable is high. That said, if you’ve got the chops, time, and cash to pull it off (the motor they used cost a whopping $275), it’s a really fun idea.
How to Charge Any USB Device by Riding Your Bike [Instructables]