"How dreadful!" cried Lord Henry. "I can stand brute force, but brute reason is quite unbearable. There is something unfair about its use. It is hitting below the intellect." ~ Oscar Wilde - The picture of Dorian Gray
I know an INTP that cracks me up, and an INTP that... occasionally make me chuckle. It really all depends. I really can only think of those two I know personally, so I have no idea if they are generally funny or not. Although I laugh at both of them because while both are complete geniuses, neither one of them knows proper English (I'm not one to talk... but at least I know there is an apostrophe in "haven't." I may or may not be exaggerating). I also laugh because they know this about themselves, and find it funny too.
Which brings up an interesting point. -WHY- are they funny? I wouldn't call my ESFJ mom "funny," but I frequently laugh at her quirky behavior.
I have an inner monologue that sounds strikingly similar to something off Animal Planet.