Unless you explicitly give permission to use your location, interested parties (like, say, advertisers) can only track you with geolocation to within a radius of about 200 kilometers. But researchers in China and the U.S. have figured out a way to get closer--much closer. With a three-stage system using Google Maps, these researchers can, according to New Scientist, get as close as a few hundred meters.
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.