The last time you walked to the store or even went on a long bike ride with friends you generated a decent amount of energy. Yet that energy probably just burned off and wasn't captured in any meaningful way.

A Chicago-based company called AMPY wants to harness that self generated power and funnel it back to your smartphone, or any device. Founded by three Northwestern engineering PhDs the Post-It sized product is simple: it captures and stores the kinetic energy generated by motion. When needed, plug in your phone.

And as the company says in their tongue and cheek Kickstarter video: That's all there is to it. You move and you plug. "We're trying to fit seamlessly into your active life," CEO Tejas Shasty says, noting their target demographic for now is active urbanites. While running from meeting to meeting, users would keep AMPY in their pockets in case they need emergency juice. "We want users to forget about battery life."

This is not the first attempt at extracting gadget power from kinetic energy. Movement is an obvious form of energy and there have been attempts to harness everything from a yo-yo to the motion of twirling something on your finger. 

AMPY has filed for patents on its technology so Shasty was hesitant to go into the specifics of what he and his team did over the last year and a half to optimize the device. They basically spent the time looking at typical inductor technology and not only optimizing the energy capture, but figuring out how to fit into a space so carrying around the device wouldn't be an issue.

Right now AMPY claims that a 30-minute run or 10,000 steps -- the amount many folks target in a day -- will provide an extra three hours of battery life for a smartphone. I haven't tested AMPY, but of course there's something a little unromantic and utilitarian about exercise now being for charging a block which then can your phone. Shasty says he wants AMPY's energy capture technology eventually built right into devices and the company is already talking with a few wearable device makers.

"We can scale it and apply it to other devices," he says. "They're all going to need power."

AMPY launched a Kickstarter earlier this month and raised its targeted $100,000 in less than 72 hours. Since then they've received almost another $75,000 and are scrambling to set up their stretch goals since the campaign still has almost three weeks left to raise money.

Everyone that owns a smartphone has that story where it died when you needed it most. This has caused charging station businesses to spring up and all sorts of new ideas on how to power the devices, such as building a solar panel right into the screen or using electricity generating bacteria. One glimmer of hope approaches the problem from the other end -- that more efficient computing processing will simply lower the requirements for batteries all together.