I was once told by someone in the restaurant biz that you can get a pretty darned good notion of the cleanliness of the kitchen in a restaurant by checking out the bathrooms. If the bathrooms are nasty.....

I think the idea is if a place is going to the trouble to keep the bathrooms clean, chances are the kitchen is being kept clean, too. That's one advantage chains sometimes have over individual eateries - their franchise standards usually call for pretty high standards of cleanliness. Not saying that's *always* true, but in my observation it has been a reasonably safe rule of thumb.