I' ve participated on a quick event in Budapest at "Akvárium". We decided to paint on cellofoil.
Also I want to give the credit where it is due:
The idea of using cellofoil as the painted surface were invented by two French graffiti artists Astro and Kanos, we thought we give it a try, and to be honest, we freaking loved it. Find out more about them at www.cellograff.com/