“It’s all good,” which it manifestly isn’t.
“Nuff said” comes to mind, but not because of the abbreviation. It usually seems to indicate a closed mind rather than a completed conversation, and when it’s meant like that, it bothers me.
“Two words:…”
MrO took mine. “Nuff Said” drives me nuts.
A whole bunch of evil intolerant people 
“Ya think?” really irks me, but fortunately I don’t hear it much anymore. Whenever someone would uses it, my response is “Constantly.”
“Well, it goes without saying…”
Then DON’T say it!
Also, any time someone says “technically” this or that, I fight off the urges to pillage and plunder their village while my head is filled with images of them running out from their burning house with several well placed hefty spears in their torso.
Yes, I’m a Doug Adams fan
“Oh no, he did-int!!”
Said with hand held up in front of face, diva-style.
I HATE that.
“Literally” - there was a funny sketch about that on Mad TV.
I second the “literally” train of thought here, but only because very, very few people on this planet seem to know what it means…
Most people think it means “figuratively”… which is the opposite…Nuff Said. (Can’t resist sometimes, deepest apologies.)
Seriously what I find most obnoxious is the use of the word “gay” as an adjective meaning stupid or lame. So many people I know say it, and it seriously offends me. I’m not gay, so I can’t even throw a personal fit, but each time I hear it, I gasp that people are willing to say that just because they don’t mean it in a derogatory sense then it’s not offensive to anyone – That’s Ludicrous!!
“You can say that again.” I don’t like having to repeat myself, so I’m not about to honor a request to do it.
“Basically” also grates on my nerves. I try to avoid using this word myself. A couple people in the office tend to overuse the word “essentially”, which, in this context, is interchangeable with “basically” and just as annoying.
I hate it when people add on “, no?” at the end of a sentence, as in, “That was an interesting discussion, no?”
“Later” used as one of the most unimaginative ways to say goodbye. Using this one with me is guaranteed to get that person’s name permanently included in my top ten shitlist entries; saying “later, dude” or “later, alligator” will get that person into the top five. I don’t mind if someone just says, “see you later”, although “later” is completely superfluous. I mean, when else will that person see you again?
I have a very low tolerance for people who inject foreign phrases into English as an attempt to sound more refined or sophisticated. This includes people who say, “adios”, “ciao”, etc. Do people who regularly speak Spanish say “goodbye” just because they think it sounds cool?
“Mighty white of you.” Geez! I hate that!
Can I use ‘literally’ to mean ‘literally’ and am only banned from using it to mean ‘figuratively, but very much’, or is it totally out?
I mean, what do you say when someone is literally climbing the walls?
One that’s occassionally seen in these forums, too: “Am I the only one that thinks ____________?”
ESPECIALLY when it’s usually found out that no, the one presenting the question isn’t nearly the only one.
“Whatever!”
Another vote for being called “brother” by anyone who is not actually my brother. Since I have exactly 0 brothers, noone should be calling me that. Ugh…sooo annoying!
–==Mike==–
“In a word…” when they use more than one word (more common in writing than speech)
“Not to mention…” You are mentioning it!
I believe the expression “jumped the shark” has jumped the shark.
“I can’t believe no one has mentioned …”