Whether you're prepping for apocalyptic end times, surviving a power outage caused by aliens chewing on the power lines, living off the grid, or just leisurely out camping, keep your cell phone and other USB devices at full power without relying on the sun or cranking on some dynamo, just use the this cool new PowerPot - Thermoelectric Generator. Simply fill the pot with water, place it over any heat source including an open flame, plug in your USB device, and enjoy the free power (and boiling water). It features three feet of heavy-duty, flame-resistant cable, a solid-state 5W voltage regulator, and a standard USB port. It can also be used as a regular pot for cooking, but for USB charging it needs water, soup, or other boilable liquids inside. Now all you need is to learn how to start a fire.
PowerPot - Thermoelectric Generator Converts Heat To USB Power