Terry Pratchett and the con sequitur.
Why do elephants paint their toenails red? So they can hide in cherry trees.
I once bought a book of surrealist humor, and boy, non sequitur jokes lose flavor faster than yesterday's gum unstuck from your brother's bedpost. Terry Pratchett has mastered a different, funnier trick I call a "con sequitur", with "con" as in "con man" or "confidence trick."
That is, Pratchett sets you up with some confident sense of what he's about to say--then, just as you glimpse the banana peel under your foot, he sneaks up and pulls the rug out from under it. You end up someplace you never expected to go--though it makes perfect sense, now you come to notice. Some examples:
(The wizard) "drew himself up to his full width..." (Equal Rites, 181)
(Granny Weatherwax thinks about bringing her goats to the slums of Ankh-Morpork) "The smell might be a problem, but the goats would just have to learn to deal with it." (Equal Rites, 165)
"Granny had nothing against fortune-telling as long as it was done badly by someone who had no talent for it." (Equal Rites, 187)
"...the far reaches of the multiplexed cosmos known to the few astrophysicists who have taken really bad acid." (Mort, 49)
My own non-sequitur here: I discovered Discworld just before leaving for Sweden, and I was disappointed that Uppsala's English bookstore had no Terry Pratchett in its sci fi section. I was disappointed until I noticed they had given Pratchett his own separate little bookcase. Woo hoo! If you aren't already an addict, I urge you to try one--just one. I started with Light Fantastic. But I can quit anytime I want, honest....
[Betsy Devine: Funny Ha-Ha or Funny Peculiar?]