The iGlassware prototype senses when it's almost empty and signals for a refill. Working like a capacitor, the glass's sides are the conductive plates and your beverage the insulator. As the glass nears empty, a microchip sends a wireless alert, along with the glass's unique ID, to the wait staff.
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.