One of my friends had me over once, and the first thing I noticed was his puppy rolling around in a litter box, only to walk two feet and roll on the carpet. Five minutes later, he made a sandwich, and asked if I wanted one. I declined, but I noticed the lunch meat was discolored. I asked him about it, he said "Oh, that's probably because it's been sitting there for a couple years." And then continued to eat it. The counter had bread, crackers, and what I hope was water scattered on it. The carpet had dirt, mud, and cat litter everywhere. And the tv remote had some weird brown grime on it. That was the first thing to come to mind...