I've seen my fair share of graffitti whilst having to relieve myself in public restrooms. I can't speak for the ladies but in the gents toilets the graffitti itself isn't all that charming it usually consists of obsenities or telephone numbers scratched into whatever surface is available (presumedly with the help of a key, coin or knife blade) along with whatever sexual service they are willing to provide the occupant of the cubicle.
However Library toilets seem to have a higher class of 'artist'.
