Cheeky sales guy: What about adding fluoride to water..?
Sales lady: Don't do it!
Cheeky sales guy: The Nazis used it.
Sales lady: Stop egging him on!
Sales guy #2: Yeah, the first place it was used was the concentration camps. Adolf Hitler found that it mellowed them out.
Cubicle neighbor: And their teeth looked awesome?
Sales guy #2: No, it has nothing to do with teeth! It's the second most poisonous element. It's used in all kinds of rat poisons.