I told my girlfriend the following joke the other day:
"An infinite number of mathematicians walks into a bar. The first one orders a beer. The second one orders half a beer. The third one orders a quarter of a beer. It continues that way until the bartender interrupts to say, "You are all a bunch of idiots," and pours two beers."
While she greatly enjoyed it, her response was, "You know, when I tell that joke I am going to specify at the beginning that it is a countably infinite number of mathematicians, just to avoid any initial confusion."
The thought never even occurred to me. I guess my brain still hasn't fully registered that there is a difference between countable and uncountable infinity. Sigh.