Remember that ballon challenge DARPA issued back in 2009 to see how quickly a team--or even a crowd--could work together to locate ten red balloons placed randomly around the U.S.? Here’s what we wrote about it then: “Most DARPA challenges serve some sort of obvious military or intelligence purpose. But the agency has us scratching our heads over its latest competition.”
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.