Sing London is one of the many reasons I love living in London. 30 painted pianos with the words 'Play me, I'm yours' have been installed across the city with the aim that people just wander over and start playing.
The other day I came across one for the first time, outside Liberty on Carnaby Street. The guy playing was amazing and even though it was raining, he managed to stop people in their tracks. He also picked up quite a lot of loose change (although I'm not entirely sure this is the point of it all!)