Taking London eight steps at a time

I found this when I was looking for interesting things about London for a friend who has just moved here: Urban Earth documents cities by taking a photograph every eight steps, and then puts all the images together to make a film. It took the photographer two days walking across London to compile this, and the result is strangely compelling - not least because the streets look so empty. Other cities you can 'walk through' include Bristol, Mumbai, Mexico City and Guadalajara (that's in Mexico too) - and they're looking for volunteers in Manchester or Newcastle right now.