LAS VEGAS: A little exercise not only does your body good, it can charge up your smartphone. Evanston, Illinois-based Ampy showed off its Ampy Move, a wearable battery pack that charges with up and down motion that makes a couple of magnets bounce up and down inside coils.

That’s an electricity-creating process invented by Nikola Tesla in the late 1800s. And on a small scale, it’s good for a quick boost of energy that can get you to the end of the day with power.

One hour of jogging while wearing the pack will get you roughly an hour of power for your phone (under normal use). The crowd-funded company has been selling them for $99. Director of marketing Ethan Krupp says a new product is in the works that is slimmer, more efficient, and has more indicator lights that give you a better sense that even 15 minutes of bouncing is creating some juice.

Source: http://goo.gl/RZEj8n