Take a look at Forza's material talk at GDC for a bit more advanced look at car paint shaders. Theres some code there if I remember correctly from attending the talk. Was a good talk about their material system.
here's the TED talk with a french artist about street art. worth a watch! http://www.ted.com/talks/jr_s_ted_prize_wish_use_art_to_turn_the_world_inside_out.html
Interesting talk and I haven't seen it around; so, I thought I would share it. http://www.ted.com/talks/jane_mcgonigal_the_game_that_can_give_you_10_extra_years_of_life.html