Hey! What's with all the white bikes?

White bikes have been appearing all across London. Look..

Me, Tachy + Jamie spotted one on the junction of Farringdon Road + Goswell Road at lunchtime today.

Then, just now, as my bus pulled in at the bus garage at Streatham Hill I spotted one chained to the railings there (pic above).

Why they are here is a mystery.

There is one clue though. And I had to walk the opposite way to home to discover this. On the bike are these words 'Life is not measured by the number of breaths we take, but by the moments that take our breath away'.

Hmm. Any ideas?