The Bottle Bank Arcade is a recycling bin that encourages a higher rate of returns by rewarding bottle recyclers with musical notes and tons of fun. It’s one of several kooky and kinetic entries in The Fun Theory competition, which will award £2500 ($4185) for the best idea that proves “fun is the easiest way to change people’s behavior … be it for yourself, for the environment, or for something entirely different.” Registration is currently open and the Contest closes Dec. 15, so enter your project today!

+ The Fun Theory