Bark beetles plague the forests of Canada so furiously you'd think rivers of blood and the death of the firstborn would follow hot on their heels. So far, no one has stopped the beetle rampage that has destroyed 33 million acres of trees in British Columbia. However, scientists at Northern Arizona University (NAU) may have devised a way to turn back the beetle tide using sound recordings.
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.