No, It's Not Mime Disease, It's Brand Interaction.

At Piccadilly Circus in London, McDonald's has a dynamic billboard that stimulates both engagement and viral behaviour.

Playing on the irresistible human desire to pretend to interact with stuff that isn't really there, the billboard randomly flashes things like umbrellas, bouncing soccer balls, dumbbells and thought bubbles -- all waiting for some eager pedestrian to position his head and/or arms in just the right spot so some content-starved intrigue-seeker can snap a shot for mom and dad at home.

Orchestrated by Leo Burnett. See vid.

Brought to our attention by Ad Broad, who rips the text right out of our fingertips when she muses, "What is it about London that inspires out-of-the-telly-box thinking?"

Because lately, London seems like the sponsored playground of the world: T-Mobile brought breakdancers to Liverpool Street Station and karaoke to Trafalgar Square; meanwhile, ABSOLUT's using the city as Ground Zero for its kindness as currency project.