Spend hundreds on hi-fi earphones, and they had better last. But even pricey pairs get tossed around like keys. Sleek Audio already started a durability trend with detachable cords that can be replaced if broken. Now its SA7 model is the most hard-wearing overall design we’ve seen.
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.