Remember attaching playing cards to your bicycle wheels as a kid, just to listen to them flap past the spokes? Here’s the grown up version: a kinetic energy charger that fits on your bike in largely the same way, harvesting juice from your ride to power your portables.

The i-Green concept by designer Fandi Meng (which comes to us via Yanko Design) fits easily on your bike, and features a little blue turbine-like deal that folds out when you’re ready to ride. This attachment catches each spoke of your wheel as it goes by, turning like a water-wheel as you power up hills and speed down them. Once you reach your destination, simply snap off the i-Green, plug in a wire, and power up your cell phone, iPod or GPS system.

image via Yanko Design

This seems like a great, simple, commonsense solution to harvesting energy on the go. After all, if we’re already expending the energy necessary to power a bike, why not power our portables, as well?

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