You may be able to cut your dependance on electricity, and kill those pesky power vampires for good . . . at least when it comes to your iPhone. The RollerGen iPhone charger just received a nod as a finalist in the 2010 Greener Gadgets Design Competition, and uses the power of your legs to charge your favorite gadget. Just attach the specialized rack to your bike, and roll on, sister — the power generated by your movement will juice up your iPhone, no power-sucking outlets needed.