For some reason, I’ve been using the word “Spiffy” a lot. I caught this from someone in my family, but I’m not sure who, since we all became infected at about the same time. I’ve made it my Life’s Work to spread the infection around so people don’t think I’m some kind of bizarro-person.
After it catches on, I’ll start spreading the appropriate reply, which is “Spiffy Doodles? I had those for lunch the other day.”
Hehe, cheese log, that’s a gooder.
One of mine is, “I’m starvin’, Marvin.” And, “Are you ready, Freddie?”
I thought of some more:
“Freezin’ or burnin’, starvin’ or stuffed” - for folks who always see the glass as half empty
“A thirsty man with a well does not thirst for water” - my dad used to use this a lot, and it never really made sense to me. Now that I have a child, it makes a lot more sense. I find myself saying it too - like when a child with two pancakes on his plate objects loudly when I take the last one off the serving tray.
From Firefly, I say “shiny” (all the damn time) and “gorram” (not so often, don’t worry).
I love saying “flip a shit” (as in “If we spend the whole rehearsal on the Copland again, I’m going to flip a shit.”) Also “Oh, for fuck’s sake,” which I got from Eddie Izzard.
Most of my weird exclamations come out when I’m either frustrated or shocked.
“Shit on a stick!” is something I say to something fairly minor, like dropping something on the floor.
If the thing I dropped breaks, I usually use “Oh, fuck a duck!” Something tells me my birds don’t appreciate this one.
And “Holy shaznitz!” is great for a variety of situations. “What the bloody shaznitz?!” works well too, but you’ve gotta say it with feeling.
I’m really pissed, though, I usually settle for a good old fashioned “FUCK!!!” 
I sometimes pronounce “mother fucker” as if it were a french phrase: “Mothair Fu-Quair”.
I’m fond of describing what comes out of my air conditioner as “coolth”.
To my cat: “You should be beaten- perhaps even eaten!”
A “disastrophe” is when everything goes wrong at the same time.
“Dain Bramage” is when I have a moment of premature senility.
“Oh Man! We’re Ten Shades of Fucked Now!”
Your excessive usage of f-words would probably disturb me would we ever meet in real life. Oh well.
I admit to doing sound effects and doing Vito Corleone impersonations in front of the mirror, but I’m mostly very low-key.
If I am outside my area of expertise, I “don’t know my ass from page eight,” or occasionally, “from Thursday.”
If something breaks, I sometimes spit out “Dog PEEPEE!” (Er, that is, I spit out the expression. I don’t ever ingest actual dog peepee, although I have been known to drink Miller Lite for its low carb content.)
In moments of resignation or futility: “What can you do?..Shit in a shoe.”
A favorite of mine is “from deep center field.” (Never did figure out what it means.)
Another favorite (not in this same vein) is either saying or writing the acronym for:
Fucked and far from home (FAFFH)
Fucked up beyond all recognition (FUBAR)
This last one always made me wonder if the WWII acronym FUBAR had any relation to their knife of choice: the Kabar. Maybe it was really Kicks Ass BAR?
My favorite is “tiddly tuddly.” It is used when someone is making too big a deal out of something.
“Excuse me, I was going to sit there.”
“Oh, tiddly tuddly, there are plenty of places to sit.”
It really annoys people when you use it in an argument. I sometimes substitute “tisk tusk tiddleywocker!” Both of these are inventions of James Best, in his portrayal of Rosco P. Coltrane.
Of similar origin, I sometimes use the phrase “Now, don’t that throw your hat in the creek?” whenever something bad happens.
“Even the MOOSE isn’t enjoying this!” = “This really, really sucks”. From Typo Knig’s high school days, when they used to say stuff like “This sucks whale wang” or “this sucks moosie cock”. We decided that if something really, really sucked, it must be so bad that it was beyond pleasing anyone, even the hypothetical moose.
“Oedipus Rex” - self-explanatory, I think 
“Poor bluebird” = one of us has, erm, a bad case of digestive upset. Originated when my spouse was trying to put the best spin on something-or-other and I snarled “What happy, chirpy bluebird flew up your ass and died!”.
“Tweet” = silly way of reminding each other to look at the funny side of things when stressed. See above.
That is so many different kinds of [adjective].
That? Is [adjective].
That is such the most [adjective].
“Don’t teach your grandmother how to suck eggs.” I use this even though I don’t really know what this means… but I know what it means - if you know what I mean. 
I mean, yes, Granny is so good at sucking eggs that to attempt to teach her is near-insulting, but as to why she would want to actually suck on on an egg is what I don’t understand. Anybody want to clue me in?
When something goes very wrong or catastrophically wrong, I’d say; “Well fuck me running!” Or “Fuck me to tears!” LOL.
I’m not much to contributing to zombie threads, but I think this one is worth the revival.
I’m another ‘Bloody Hell’ American, probably use it more carelessly than the Brits do.
I also will say Raskalmikov when frustrated–which is a word I made up and as far as I know has no relation to any East European/Russian word, so I can say it and people can think whatever they want of it. Pronounced Raz-kal-mi-kov.
Jesus Fucknado Christ.
(I think it popped into my head after one of the “Sharknado” movies. Tends to emerge once I’ve lost all hope/patience and is more an expression of resignation than anger.)
Mine’s a mixed metaphor of sorts.
Off like a herd of turtles.
and
Off like a Jewish foreskin
becomes:
Off like a Jewish turtle.
or
Off like a herd of foreskins
Both make me laugh to myself and both elicit confused looks from the listener.
I got some funny looks last time I said ‘whatever floats your goat’.
I’m pretty sure I picked it up from an episode of Mythbusters (Jamie said it).
Since this has been resurrected…
Count me as another “Bloody hell!” Yank. I’ve also been known to mutter “Jesus Haploid Christ!” in trying circumstances, along with Venkman’s “Mother pus bucket!”