If you can’t afford a Playstation, or maybe just like wasting paper, then Receipt Racer is the video game for you. Created by Joshua Noble and undef, Receipt Racer is a game played on paper as it's rapidly churned out by a thermal receipt printer. It prints a racetrack with random obstacles that the player must avoid by using a Dualshock 3 controller to steer a tiny car projected onto the moving paper by a light beam.
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.