How many times have you tried to switch on a flashlight, only to find the batteries are dead? Well, here's one that works simply with the heat of your hand. All you need is to be alive -- and warm.
The Hollow Flashlight is the invention of 15-year-old Ann Makosinski of Victoria, Canada, whom we wrote about in July. Her flashlight is one of four winning creations in the annual Google Science Fair.
With more than a thousand submissions, the event highlights teen innovation around the world. The grand prize of a $50,000 scholarship went to San Diego's Eric Chen for his use of computer modeling to discover new flu medicines. … Read more