A recent article in The New York Times reported on the growing practice of "shopdropping," in which people who are promoting a product or message surreptitiously plant items in retail stores. It's the opposite of shoplifting.
Shopdroppers reportedly include religious groups that have been slipping Christian cartoons into the pages of science magazines at Powell's Books in Portland, Oregon. In retaliation, other shopdroppers have been moving Bibles from the religion section to the sci-fi/fantasy section.—Dawn Stover
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.