Doug Pray made a great video for the Paul Curtis Reverse Graffiti Project.  Green Works, the plant based cleaners, is who this graffiti advertising is promoting.  Paul Curtis is one interesting graffiti artist, he is armed with a power washer, not a can of spray paint and his canvas is a dirty surface that he sets out to make clean.  Just check out the process, it’s all pretty interesting in a green sort of way.