Tremont Electric has created a kinetic energy-based charger called the nPower PEG, otherwise known as a Personal Energy Generator. The PEG can charge a portable device up to 80% with an hour’s worth of movement. You don’t need to attach the PEG to yourself to gather the kinetic energy. It can be placed in your backpack or attached to your bike and it will harness the same energy. You can even use it while using the subway or bus.

The device weighs 9 ounces and is 9 inches long by 1.5 inches in diameter. To use it, you simply plug your phone, MP3 player or other device directly into the PEG via USB cable and start moving.