Doctors have miniaturized almost everything they need to send robots inside your brain's blood vessels to treat damaged tissue. But making a motor small enough to squeeze past blood cells has held things up. Now, engineers at Monash University in Australia have built a micromotor that brings bitty 'bots closer to reality.
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.