Designing on a laptop from the comfort of your local Starbucks is one thing. Imagine hanging from a wall several flights up, outside of a building. Sometimes even in the cold to create a giant advertisement for a company. Takes some balls, no? Balls and a paintbrush. Well, you know, and paint. These guys give some insight into what it is to be a “Wall Dog.” (They call themselves “wall dogs,” says one veteran of the trade, “because we are chained to a wall all day by our safety harness, and we work like dogs.”) Really wish it was a bit longer.