Just a friendly bump for the benefit of those who may have missed their chance before now. This was one of the more fun threads I ever started and it seems to have amused quite a few of us over time.
Add some more, if you think of them! 
I’ve never heard it before, but when my wife talks to me while I am in the bathroom, I yell back “I can’t hear you over the thunder of my piss” It cracks her up.
The things we reveal over the internet…
An expression coined by a university friend, and subsequently borrowed by me – referring to someone going away / ceasing to be on the scene: as “de-featuring”.
To be precise: the Papal Legate Arnaud-Amary, one of the Catholic commanders at the siege of the city of Beziers in 1209. “Kill them all; God will know His own.”
A thing which I came across as a kid, reading a Western novel – a character was asked what condition his horse was in: and he replied (or so I remember it) “Fine as frong hair, and full of ginger”. I really do think that the word was “frong”, not “frog” – though I might have misread it. At the time, I just thought it – in an “oh, those wacky cowboys” way – a nonsensical but splendidly descriptive expression.
Put {spoiler} in front of the first word you want hidden, and {/spoiler} right after the last word, but use square brackets - - instead of the curly brackets I used.
(If you “Quote” any message that includes a spoiler block you can see how it’s done.)
"I wouldn’t pay that much to see a pissant eat a bale of hay (or see the Statue of Liberty take a dump).
“My teeth are floating” (when I really need to pee).
“X is a household name, but so is garbage.”
“You’ve got about as much of a chance as a one legged man in a butt kicking contest.”
I’ve always liked: “If I were 30 years younger, I’d be all over her like a cheap suit!”
My mother: “Heavens to Murgatroid!” and “Godfrey diamonds!” and “I don’t care if you were with the Queen of Sheba…” and my grandmother: “He’s as deaf as a haddock.” More will come to me later I’m sure.
WC Fields had a similar Godfrey, except his was Daniels.
W.C. Fields also, when startled, would say “Mother of Pearl !”
Along that line, there’s “Oh, my Duck !” (Firesign Theater), and the ancient sailor’s “Shiver me timbers!” for when heavy wind would make the rigging hum.
“They knew not their holes from an ass on the ground,” from Firesign, which I suspect also spawned, “He knew not sh#t from Shinola, and his shoes showed the strain.”
There’s a few that are better with a step removed, “Raining like a flat rock”, “Your mama’s boots have instructions written on the heels.” …Or bent, “If beggars were choosers, then horses could ride.” “Cold as a bitch’s wit.” “Oh, I made a fox’s paw!”
Anachronistic expletives I like:
-zounds!
-gadzooks
-23 skidoo
-by hell and maria
Unfortunately, most of my peers don’t appreciate them.
“His mouth’s writing checks that his ass can’t cash.” Or as a warning “don’t let your mouth write checks that your ass can’t cash.”
When I was young, I misunderstood a coworker who said “Let go of my ears; I know my job.” I figured it meant something like quit bending my ear/needlessly nagging at me since I already know how to do/about the thing. I had quite the retroactive embarrassment when I finally got it.
Something I picked up from my yesterjob. When failing to catch what someone says: “your what hurts?” Don’t really know the origin of it.
He’s so dishonest, if you shake hands with him, count your fingers afterward.
After a good meal, I may profess myself well-gruntled.
Expressing suprise: “Well butter my buns and call me a biscuit.”
When referring to the usual household junk drawer: “Nothing in there but knick knacks and turkey turds”
Economic woes: “They’re so poor they don’t have a pot to pee in or a window to toss it out of.”
Expending a lot of effort: “He’s working harder than a three-legged dog in a forest of fire hydrants.”
All of the above courtesy of my southern-born husband.
The plural of son of a bitch is son of a bitches.
“Necessity is the mother of strange bedfellows.”
Said of a horndog acquaintance who was none too discriminating in his choice of bedmates:
“He’d fuck a snake if he could get someone to hold its head.”
When asked for my opinion and I don’t have one:
“Don’t make me no never mind, so long as you’ve got kitchen kleen potatoes”
When I want someone to stop dreaming and apply themselves to the situation at hand:
“If wishes were horses, beggars would ride”
When I’m exasperated but not angry:
“Oh for the love of the little baby jesus and all his little cheeses!”
I didn’t think this was a particularly unusual expression but I’ve since learned it’s unfamiliar to some people. I’m wont to say biffed to mean tripped or fell or just made a mistake. He biffed it!
When writing to a group of mixed sexes:
instead of “Dear Sirs/Mesdames”
“Gentlepersons”
Not “Gentlefolk”?
Nope. “Gentlepersons” it is so simple and refined.
May be ‘too cool for the room’ around here.