When filling the tank on a windy day always stand upwind from the nozzle.
I discovered this gem when leaning with my back to that car holding the nozzle on and looking at the pump. A guy walking to the booth to pay watched me the whole way from his car to the booth. I looked down to see the gas pouring out of the tank filler tube and blowing across my (freshly dry-cleaned) dress pants. The auto shut-off sensor failed to work properly. It was a very smelly drive home with windows open in a cold November.