A permanent art installation on the Rhine in Germany, Tiger and Turtle-Magic Mountain is a roller coaster with no coaster (or roller? The name roller coaster is just now starting to seem confusing.). Instead, art lovers/roller coaster enthusiasts are encouraged to walk along the path of narrow steps.
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.