Are you ready to play everybody's not-so-favorite guilt game: what was I doing at that age? Ann Makosinski, a tenth grader from Victoria, British Columbia, has created a simple LED flashlight powered by body heat. So instead of having to recharge it or swap in a fresh pair of AAs every so often, you literally just need to hold it in your hand for it to start glowing.

Makosinski has been entering science fairs since she was in grade six, and has an interest in alternative energy, particularly harvesting all the wasted energy around us. And while researching her favorite topic she came across a device called a Peltier tile which produces electricity when cooled on one side, and warmed on the other.

After crunching the numbers, she determined that the warmth from a human hand could produce enough energy via a Peltier tile to power an LED in a flashlight. And after several prototypes, a few dead-ends, and plenty of frustration, she managed to produce two working prototype flashlights—one made of aluminum pipe and the other PVC pipe—that earned her a spot as one of the 15 Google Science Fair finalists from around the world.

The parts that went into the flashlight cost a mere $26, but if Makosinski manages to win the grand prize in the science fair she'd walk away with a $50,000 scholarship. It's certainly an impressive feat for a fifteen-year-old, particularly if you remember back to what you were doing at that age. Inventing a revolutionary new gadget? Probably not. [YouTube via CBC via Damn Geeky]