The PIN digits you punch into an ATM’s keypad to authenticate your transactions are leaving traces of themselves behind in the form of heat, says a paper recently presented by a team of UC San Diego security researchers. Someone following immediately behind an ATM user can use a digital infrared camera to determine what keys were pushed with about 80 percent accuracy, their study shows. Even a full minute later the camera can pick up the correct digits about half the time.
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.