I am going state right up front that I am not crazy about using other people's bathrooms and even less crazy about people using mine. Someone pops into the bathroom and if I am not hearing the sounds of handwashing within about 30 seconds, I start to get nervous.
So, last week a visitor to my bathroom actually clogged it up, Al Bundy-style. And if that's not horrifying enough for someone like me, actually waited until the water tank had refilled itself and then, when the water level was at its absolute maximum height, flushed again (!) so that water et al began pouring out onto my bathroom floor, down the heating duct and out into the carpet in the hall. The old ball 'n' chain actually had to get out the carpet cleaner to suck the water out of the heating duct. Incidentally, I have a new name for the carpet cleaner now and that's the "no fucking way will I ever use that machine again" machine.
You haven't really lived until you spend your afternoon, running out of "rag" towels and having to revert to using your actual family bath towels (gah!) to clean up someone's overflow. As these situations tend to go, this one just kept getting better with caulking around the floor moulding disintegrating, linoleum bubbling up and water (ahem) stains being left on the ceiling in the garage. Witnessing this damage the person (who, by the way is notoriously cheap) then says, "Oh well, that's what insurance is for!"
I tell this story and my father-in-law tells me that he saw a news report that said the toilet bowl is far cleaner than the kitchen sink. Dudes, I do not know what you are putting in your kitchen sinks, but I can maybe make a few suggestions about what not to put in there, if you need some.
Moral of the story: Please don't ever use my bathroom.