I spotted this phonebox while I was walking into Stratford earlier today, which caught my eye because of the tagline 'run your city'. I'm not a runner, and I won't be signing up for their contest, but I still kind of love the idea - getting people to hit the streets and expand 'their' London. The whole idea of 'London is your gameboard' is one I can appreciate.
I know they're a running company, but it still bugs me a little that they categorise walking as 'cheating', because walking London is one of the ways that I feel that London is my city - or at least some parts of it are. That's almost my functional definition of which areas I consider 'mine' - areas that I can walk confidently from memory. Areas that I know well enough to notice what's changed, know what's new, how to get around without having to stick to a narrow known route - those feel like my city.
I do approve of people setting up games to encourage people to explore their cities, though - I never wrote it up, but I did a Photo Scavenger Hunt a couple of weekends back around Hackney, which was great fun, and has added a little more area to the parts of London I count as my own.