These pictures doing the rounds supposedly show a "guerilla marketing component from a campaign designed to gain public support in an effort to reduce the pollution released by particular powerplants in Chicago. The shape and text was created by power-washing filthy sidewalks using a large stencil form."

It would be a clever idea for an anti-pollution campaign, except that these photos look photoshopped. The border of the image seems a bit too well-defined, as do the lines of the text. Plus, if you're going to do this, where do you get the water and power source for the washer? (Unless you have a mobile washer hooked up to a van.) (via ads of the world)