When I was a kid, I remember that someone I know (it may or may not have been a family member), would illicitly dress up the statue of President McKinley outside the Dayton Public Library as Santa Claus every Christmas. It was a complex process that involved taking measurements without anyone noticing, sewing a costume, sneaking to the library in the middle of the night and dressing this much larger than life statue without getting caught, and finally watching the paper the next morning to see if the newspaper published a picture (which they did).
Well, now a related practice has been taken to new artistic heights with something called yarn bombing. The idea is that you knit something specifically for some public item/structure, then you sneakily clothe it in your custom made togs. I like the idea of keeping those cold metal statues warm on winter days with a little knitting. This is one type of graffiti I can definitely support. Any takers?
See more here and some yarn bombing stories here