Fun will change the world

What happens if you make the mundane fun? That is the question behind The Fun Theory, a project sponsored by Volkswagen.

These stairs are my favorite.

I’m not sure if the stairs play a song, or just the piano notes. I kind of want them to play a song, like this:

Other Fun Theory ideas include the world’s deepest trash can and a recycling arcade.

Entries are being accepted through Dec 15. What problem would you solve through fun?