Those one-way mirrors made famous by cop dramas aren’t actually one-way. They simply play off the differences in light on each side. That is, if the lights were equally as bright behind the mirror as in front, that rattled suspect could see right through to the cops on the other side.
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.