I've got two more:
1. "Please do not put butter or jam on bread prior to toasting" (in the dining hall at school--the next thing you know, there's going to be some idiot who thinks that margarine, marmalade, and peanut butter are fair game, lol.)
2. "Please do not clean your brushes here." (over the downstairs drinking fountain in the art building).
I know these probably aren't as egregious as "Please do not use ruins as a toilet," but bear in mind that the kinds of people who attend university are *supposed* to have been the best and brightest in their respective high schools, and should therefore have the basic common sense to know how to make toast, and to figure out that maybe other people don't want to drink nasty paint water. I think it's just entitlement, though....those people don't think they should have to wait a few minutes for their turn at the sink, which is theoretically MORE convenient, because both the painting studios (the downstairs one that the CEGEP kids use, and the upstairs one that we use) are equipped with large sinks that can easily accomodate a few people at a time....and that's *definitely* a good thing, because I don't know about the downstairs studio, but the upstairs one has white walls, shelves, and a white podium in the centre of the room (the floor is just cement, though), but the entire place is permanently stained in a rainbow of colours, not from carelessness or malice, it's just impossible for a white painting studio to *stay* white forever, you know? It doesn't bother Pablo or the other profs, but the idea is for the mess to stay confined to the appropriate areas.