Similar to Regallag’s, is the classic “Just don’t talk.”
Another simple, deep cutting insult is “No one likes you.” You could be the most confident person in the world, but if someone says that with conviction you’re going to be doing some questioning.
If you are addressing a Democrat: “Republican!”
And vice-versa.
From Invader Zim (and thus safe enough for Nickelodeon): “Shut your noise-tube, taco human!”
I find myself using these quite often (tongue-in-cheek, because they probably aren’t very effective anyway), both from Dodgeball:
You’re adopted, your parents don’t even love you.
and
You’re about as useful as a poopy-flavored lollipop.
My Old Man used to say to me “You’re about as helpful as extra ugly on a warthog.”
Sometimes, “extra lumps,” or “extra tits.”
This is a battle of wits, and…
…you volunteered as a stretcher bearer
…you brought a knife to a gunfight
You…
Got hit with the ugly stick
Fell out of the ugly tree, hitting every branch on the way down
are a card carrying Member of the ugly Forest Basejumping Team.
I’d suggest you were of equal worth to pond scum, but I think pond scum produces oxygen.
you rate higher on the food chain than (other stupid guy) - but only because i think you could eat him, lardy.
You’re the Durex Poster Boy
(mutual enemy) said you weren’t fit to sleep with pigs. But as I am your freind, I stood up for you. I assured him you were.
Personally, i’d be pretty offended if anyone called me a liberal :eek:
For some reason “shut your pie hole” has always oogied me out. On the other hand I really like “you are a waste of my air.”
My personal favorite is “Shut your filthy pie-hole.” I think the “filthy” really adds something to the image.
Borrowing from Red Dwarf, another favorite is “We all have something to bring to the conversation. Fron now on, I think you should bring silence.”
I like 'em long and obtuse.
Said in anger to a very liberated female friend:
“Don’t you have dishes to do?”.
The one that really, really annoys me is non-verbal (and in my experience most commonly implemented by high-power career folks, whatever the hell that means…) - it’s the stop-talking-because-I’m-going-to-speak-and-the-world-must-hush-and-listen gesture.
You know; manager demands an explanation as to why the widgets aren’t on display yet, in your zeal to give a complete and informative answer, you begin by saying “Well, I’ve been checking the deliveries for a week now and chasing the suppliers six times a day, but despite their promises, the widgets haven’t arrived yet”, except you only get as far as saying the bit in red, when the manager abruptly presents your face with his outstretched palm and says “I didn’t ask you for your life story, just tell me why the widgets aren’t on the shelf!”
After that, a lengthy interrogation ensues as to
Why haven’t you checked the deliveries? / I have checked the deliveries
Why haven’t you chased the supplierd? / I have, six times a day
Well why didn’t you tell me that in the first place? / Because I would have to cut off your fucking ARM in order to complete a sentence!
I’m a fig ban of the spoonerised insult.
For example:
“You bon of a sitch”
or
“You chit-eating sockcucker”
not that there’s anything wrong with cucking sock
wrenchslinger
I refuse to have a battle of wits with an unarmed person.
I’ve always been partial to “Son (or daughter) of a syphilitic whoremonger”.
Robin
“Oligophrenic” works wonders.
Ieuuuu.
Here’s one that I’d rather not hear: lung butter. Geez, boss, I could have completely done without that image–it grosses me out just typing it. Fortunately, he doesn’t interject it into everyday conversations, just when he’s discussing what he coughed up, but I’d much prefer to hear “man, I got a lot of shit in my chest” instead of “man, that was a wad of lung butter.”
Awww. That brings back such fond memories! An old friend of mine used to use a variation of that phrase (burping in place of guzzling) all the time. Not, I might note, directed at me, that I recall 
Would “lung cookies” improve the visual? My husband introduced me to this term. I have fallen in love with it.
“I hope someone you love dies.”