In a disaster, cell phones are not even as useful as the antiquated land line -- towers might topple, and service may jam as people overload the system with calls. Australian researchers tested a new system last week that aims to solve this problem, as well as introduce cell phone coverage to remote areas. It essentially uses cell phone swarms, enabling regular mobile phones to make and receive calls without cell towers or satellites.
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.