"Smart" floors that monitor your movements might not be practical for a while yet, but this one seems like a lot of fun. The GravitySpace floor monitors your weight, and beams a mirror image of yourself back. After that, the image can do some neat activities, like play soccer. It could even perform customized functions just for you, like turning on your favorite TV show when you sit down on the couch, or monitor itself for unfamiliar footsteps, keeping you safe from intruders.
The glass floor is surrounded by infrared LEDs covered with pressure-sensitive film. Below the glass floor is a camera and projector. When someone steps down on the film, it stops the infrared beams. The camera notices that, and the projector can beam up an image (or move a soccer ball) in response. Presto: quality time with your mirror self.
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.