The DIY miniature satellites known as CubeSats have a lot going for them. They're cheap, they're easy to program, and they're small. That last benefit also adds a downside, in that the CubeSats are too small to sport any propulsion systems. MIT is looking to change that by creating an ion propulsion system so small that it will take up less than 10 percent of the already tiny Cubes.
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.