An infamous nun in the Seton Keough community in Baltimore County, Maryland was actually called "Hell on Wheels"-- because of her name (Sister Helen Mercedes, which was obviously to pun) and her reputation for cruelty toward students at Seton Keough High School (which was two separate schools while "Hell on Wheels" was there).
When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).