There was a kid going around tagging Lord Big Time Pimp the Great. I always thought it was a shame about his self esteem.

A cartoon punck rocker with Mohawk,boots,spikes all the trimmings but he didn't have arms
It read "I'm so punk rock I don't have arms!! OI OI OI" I wish we could post pictures in the comments

There was a piece of graffiti painted on the support of a bridge near my home that featured the mascot for Quaker Oats and the words "Make oats not war" scribbled next to it. I still laugh about it though it's since been removed I think.

"C.R.U.D. Gang Related" (the news in portland was going crazy over 'gang' graffiti back in the early 90's, so we went and spray painted "C.R.U.D. Gang Related" in about a dozen or so different spots all over the portland area....and made the news....there were three of us....oh, and C.R.U.D. stood for Chaotic Radicals Undermining Democracy...though, all we were really undermining was the local liquor population.

Best I've seen... see pic.