Clean (with plain water) graffiti verstising by a Dutch Company called GreenGraffiti.

“Armed with just a template and a high-pressure water sprayer, the company has “cleaned” advertising messages out of the dirt on behalf of clients including Elle, Telfort and Universal Music. No paper, no ink, no printing process—GreenGraffiti’s ads are completely carbon-neutral, it says. springwise.com”

Check there website GreenGraffiti. I’m defiantly keeping there service in mind!