My wife and I have separate bathrooms, but she walks by mine on the way out of the bedroom. Every few days, she notices the sink in my bathroom is dripping (or even running at a slow trickle). When this happens, she of course thinks I am being careless about turning the faucet off, and she lets me know it rather enthusiastically. Now, I am the first to admit that I am absent-minded and capable of leaving the faucet on. However, since she scolds me rather severely every time it happens, I am being VERY careful to make sure the faucet is off when I leave the bathroom. I think it's fairly unlikely that I'm leaving it running. But I have to admit, I don't know how it would start by itself, and she doesn't use that sink. Does anybody else have any other explanation, other than that I have to be even more careful?