Siva Atom Bicycle USB Charger
Get a little extra out of your next ride with the Siva Atom Bicycle USB Charger. This clever gadget attaches to your rear hub, transferring your momentum into energy you can use to keep your USB devices charged and keep the included, detachable 1650mAh battery pack juiced up. It installs easily, doesn't offer so much resistance as to slow you down, and is weather resistant, so you needn't worry about running over a puddle or two.