We've long enjoyed the works of British artist Luke Jerram and are especially impressed with his interactive public works, such as this enormous slip-and-slide down the middle of a city street and his singing metal sculpture. So it should come as no surprise that he's the mind behind Play Me, It's Yours, an ongoing project to place beautifully decorated pianos in public spaces. Anyone can sit down and play at one.
It's become a movement far beyond Jerram's work alone. There have been 1,300 pianos in 45 cities on 5 continents. You can find a map of them here and photographs of the more colorful ones at My Modern Met.