In London, maybe ten years ago, if memory serves right, there was a graf artist named Sha who was also a fairly prolific tagger. Whilst I've never had a great deal of respect for the tag outside of placing it beside graf itself this is one tag I always remembered.

It was simple enough but highly effective and just had a certain bit of comic oomph.

A large S shape was drawn almost as a circle, just the slightest of curls to give away the letter itself. You almost didn't notice it because what drew your eye first of all was the center which had a simply drawn

HA!