But regardless of name, lexical categories are quite useful. They make possible not only Mad Libs but also the rhetorical device anthimeria — using a word as a noncustomary part of speech — which is the reigning figure of speech of the present moment. [Emphasis added.]
Mister hardcore grammarian writes one of the most most offhand belly-splitting-with-laughter phrases of the year! Mad Libs! I bet grammarians fill out the most ridiculous Mad Libs in their spare time.
--Charles, look at this Mad Lib I filled out: 'After a sesquipedalian micturation, Bobby cogitated that his turkey had become an inextirpable ossification.' Har har, I'm such a latitudinarian!