Fry an egg with a solar-powered backyard death ray
The idea of focusing the sun's rays into a concentrated beam of heat using a magnifying glass is so well known that all you have to do is say "ants under a magnifying glass" to conjure the image of a torturing bully.
Backyard tinkerer Grant Thompson isn't a bully, but he does have a giant magnifying glass. More specifically, he has a Fresnel lens -- that is, a giant lens made of corrugated concentric circles adapted from an old rear-projection TV. … Read more