This really is one of my favorite jokes:
Two nuns, Sister Mary Agnes and Sister Mary Vincent, are traveling through Europe in their car, sightseeing in Transylvania. As they are stopped at a traffic light, out of nowhere, a small vampire jumps onto the hood of the car and hisses at them through the windshield.
“Quick, quick! shouts Sister Mary Agnes, What should we do?”
“Turn the windshield wipers on. That will get rid of the abomination”, says Sister Mary Vincent.
Sister Mary Agnes switches on the wipers, which knock the mini-Dracula around. But, he hangs on and continues hissing at the nuns. “What shall I do now?” she shouts.
“Try the windshield washer. I filled it with holy water before we left the Vatican”, replies Sister Mary Vincent.
Sister Mary Agnes turns on the windshield washer. The vampire screams as the water burns his skin, but he hangs on and continues hissing at the nuns.
“Now what?” shouts Sister Mary Agnes.
“Show him your cross”, says Sister Mary Vincent.
“Now you’re talking”, says Sister Mary Agnes. She then opens the window and shouts, “Get the fuck off our car!”