It’s time for spring cleaning, so I started looking around for the best technology to tackle my dirt. It turns out I may already have it in my refrigerator—or possibly in that half-drunk bottle of wine on the counter. Simple vinegar can apparently clean toilets, kill weeds, fight dandruff, scare off ants, lift deodorant stains, and keep the white from running out of a cracked egg. The acetic acid in vinegar—produced when alcohol ferments—turns into a grease-cutter as powerful as commercial cleaners, according to the Vinegar Institute. (The what? Seriously, there really is one.) Makes me wonder what my salad dressing is doing to my intestines, but I’m too caught up in vinegar trivia to care. —Lauren Aaronson
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.