guy2: Yep, still not as bad as Gwen Tennyson blowing an alien while getting fucked by her cousin, mother, and grandpa at the same time!
guy1: Daaaaaammm! rule 34 strikes again!
guy2: Thank god there's no "Chuck Norris fucking Optimus Prime" shit out there.
guy1: You just imagined it, now there is.
guy2: Damn you rule34, damn you!
Additionally it is accepted that the rule itself has limitations and you cannot be too specific on the content of the item in question.
Most commonly used on various message boards for various reasons, from humor to cruelty.
You cannot be 100% specific about this rule.
I saw a rule 34 of Micky Mouse and Optimus Prime - Wrong.
(Please note, since I have suggested the second example, it is now being worked on by Insane Japanese Hentai Anmiation Artists)
Known exceptions are:
Rule 34 itself. You cannot rule 34, rule 34.
Also, abstract ideas may not be rule 34'd, it must be a concrete object or be representable as one.