Many expressions of art today and throughout history is not acceptable by society or is necessarily legal. In the Art of the MOOC video lectures 2.1, the Gorilla Girls were mentioned. This reminded me of expressions of art that are anonymous. I would put public graffiti in this same category. Graffiti is not legal in many places and can be a beautiful expression of art, normally expressed in the cover of darkness.
a wiki of socially engaged art
