UK organization Hubbub plans to clean up the streets of London through its #neatstreets campaign. One clever project sees smokers vote on various topics by placing their cigarette butts into clear divided containers in public areas; another uses devices that play music when a cigarette butt is inserted; and yet another encourages gum-chewers to connect the dots on specially designed boards.

"Our public polling discovered that a staggering 86 per cent of people think littering is a disgusting habit yet only 15 per cent of us would actually confront someone and tell them that," the organization writes on its webpage. "This is why from May to October we're trialling a new approach to tackling littering on Villiers Street, Westminster, using the latest thinking on behaviour change and awareness raising from around the world."