Reverse Graffiti - Green Trend in Street Art

Artists draw inspiration from a variety of sources. One trend that caught my eye recently is the idea of reverse graffiti. Street artists are cleaning surfaces in order to create artwork. The piece is created by cleaning away the dirt on a surface and the difference between the dirt that remains and the surface that was cleaned is so striking that the artwork has the same presence of a traditional graffiti/street art piece.

A green design site named Inhabitat has a nice article with photographs of some of the pieces.