If you're walking along one fine summer day, and happen to look up in the air and see a giant cursor pointing down at you, do not freak out. Tron is just a movie, you are not a program, and that giant cursor is just a giant kite. Flown by a giant nerd. And since the company that makes the thing, Windfire Designs, prices its kites pretty reasonably, chances are that giant nerd pointing at you with his cursor kite will be me.—Joe Brown
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.