[Video:http://www.youtube.com/watch?v=isfrCIhQ5HE]
 
These guys from Vienna, members of the Graffiti Research Lab, created a ‘green way’ to make graffiti in the city without damaging buildings. With a laser light they can draw whatever they want on big buildings and their sketches are erasable with one push of a button. It’s better for the environment than aerosols and an innovative manner to be an artist without annoying other people.