Not the most ergonomic power-bank/external-charger we’ve seen but definitely one of the innovative, ambitious sorts. The Double E power bank turns motion into energy with its internal dynamo. Give it a few good shakes and you’ve got juice for your phone or tablet! Of course you can charge it the traditional way too (via MicroUSB), but that’s too boring. The form-factor features a cylinder with an intersecting cuboid. On the front of the cuboids are two outputs and one input. It also has an LED matrix that displays the power bank’s battery in a percentage format so you can see the power build up when you shake the gadget around, and watch the power drain when you’ve got a phone plugged into it. Not the smallest power bank we’ve seen, the Double E’s size comes from the fact that it has a moving magnet and a copper coil on the inside to generate electrical energy. I wonder how much power it could generate though. Any thoughts? Designer: Zheming Zhou