Eric Fischer analyzed thousands of photos of New York. Based on the historical data from each uploader's Flickr account, he deduced which were taken by tourists and which by locals, and plotted the results on a map.
Now we've turned the geo-data into a game. Can you figure out which photos are which?
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.