There is a Denny's in my town that we are pretty sure is just a drug laundering front. It's been open for years but there are never cars in the parking lot and the two times we have gone there were two servers in the whole place.

One year an ice storm knocked our power out for four days and, in desperation, we went there for heat and hot food. There was one other table sat at the time. We waited about 90 minutes for lunch for our family of four - it was nuts!