Clean Green Street Art

Now this is an interesting take on graffiti:

A number of street artists around the world have taken to expressing themselves through an innovative practice known as Reverse Graffiti. Taking a cue from the “Wash Me” messages scrawled on the back of delivery trucks, they seek out soot covered surfaces and inscribe them with images, tags, and even advertising slogans using scrub brushes, scrapers and pressure hoses. [read more ...]

More discussion on reverse graffiti can be found at MetaFilter, which is where I found this article.