Always guaranteed to make me smile (at the very least) are contrived rhymes, as in:

"Do whatever steps you want if
You have cleared them with the Pontiff"    (Vatican Rag, Tom Lehrer)

and (the most recent new example I've heard):

"And although your hair is greying and you're glad to be alive, it's
True a touch of romance can still stimulate your privates"

(Nifty When You're Fifty, Tony Winn).

I don't know if there's a technical name for this kind of rhyme, where one half of the pair is formed from at least two words (usually not nouns) and the other from one word (usually a noun). Whatever it is, it works particularly well, scattered here and there, in humorous songs.

- jeanie