My absolute favorite was the one my grandfather used to tell me, he would say "Boy if your gonna be dumb, you gotta be tough and you are, by far, the toughest kid I know" I love the back-handedness of the insult.
The other one that I think is funny is due to Tombstone most people think it is: "Im your huckleberry" when in fact the correct term is "I'll be your huckle bearer" which is the equivalent of a pall bearer, in the south we call the casket handles huckles. The term basically means keep it up and you are going to get the fight you are looking for.
Not the term, a term. They're different idioms with completely different meanings, both well-attested historically. "Huckleberry" is not a corruption of "huckle bearer" here or anywhere else.
Doc Holliday isn't quoted as having ever said the phrase, by the way. It's taken from historical fiction, in a context where "I'm your huckleberry" -- "I'm game", "I'm up for it", "I'm your guy" -- makes far more sense.
"They say you're the gamest man in the Earp crowd, Doc," Ringo said. "I don't need but three feet to do my fighting. Here's my handkerchief. Take hold." Holliday took a quick step toward him. "I'm your huckleberry, Ringo," replied the cheerful doctor. "That's just my game."
https://www.google.com/books/edition/Tombstone/4PnFRfNtyhYC?...
This simply isn't true. It was a common phrase and is widely attested in texts from Holliday's lifetime.
You originally said:
> due to Tombstone most people think it is: "Im your huckleberry" when in fact the correct term is "I'll be your huckle bearer"
I'm not arguing that "huckle bearer" wasn't also a common phrase. It's just not the "correct term" here. There's no basis for the idea that "huckleberry" was either a misquote or a corruption of "huckle bearer". Both the immediate textual context of the novel and the broader historical evidence for the phrase clearly establish otherwise.
The movies use of them was actually well played as Holiday was from Georgia and would have shared many of the colloquialisms that where in use in the deep south of Florida, Alabama, Mississippi, etc.
"Faster'n a pack o' dogs on a three-legged cat"
The equivalent deep south colloquialism for that would be: faster than a raped ape. I don't exactly understand why apes are so fast when they are raped but apparently they are fast. The other one I hear, but not as much, is faster than a knife fight in a phone booth.
One of my other favorites that is tangentially related is:
Ya'll cover your ass faster than the new guy on D'block.