When you are completely roasted toasted and caught by surprise. A term you should not often use as you should always have an ace in your hole. Hopefully, when you do use this term, those around you will be so completely and utterly destroyed both physically, mentally, and spiritually that they'll bow down and worship you.
Teacher: "Did you say further? Further means more and you can't be even more of more; the proper term is 'farther!'"
You, me, or any enlightened child: "Well slap my ass and tickle my pickle, I'm going to kill myself!"
Thicc Boi: "WHO GOES NEXT? If he's on my left and he's on my right, WHOSE IN THE MIDDLE??
Enlightened one: "Well slap my ass and tickle my pickle he's got more chromosomes than me!"
When a statement or a joke amuses you to a point, to an extent which would fill you with warmth and make you grin broadly, but not necessarily laugh. It gets you in a personal place. Perhaps it appeals to nostalgia, or it's simply a joke that only you find funny, or particularly resonates with you for no apparent reason.
Bob laughs at something for ten minutes.
Bill: How can you find it that funny?
Bob: No idea, it just really tickled my pickle.
What tickles my pickle is how I can see through that door from all the wayover here, but when I get up close to it I can't see a damn thing through it!