“Puckernuts”, from the Elfquest comic. Or if I’m really mad, “Raggin’ Fraggin’ Nutpuckers” from spoof of same. It has also supplied me with “twedge” for certain kinds of people and “zug” for when the zugging thing gets all zugged up and “threk” for when you don’t know what the threk is going on, but I don’t use those last two so much.
Fudge a muffin! Oh shhhhhh…ag.
“Son of a gun” works as does “God Bless America”.
Chinese or Taiwanese swear-words for when I’m in the company of unsuspecting foreigners, or “Frick” or a low hiss (AKA an aborted “Shit”)
If I’m not in a “hurry” (that is, I have enough time to control my mouth), I say “Goddess bless” or some random Tolkien Valar’s name (Often Elbereth or Manwe)
“Shiite Moslems!”
“Sheesh Louise!” (even my kids say that one)
“What the hey-hoo!”
“Bally” (as in “the bally balliness of it makes it all seem so bally…bally!”)
“Son of a beehive.”
“Mother Machree”
“Genius”.
I started saying this after realising that exclaiming “Jesus!” was deeply offensive to some people - I think it was after a thread on these boards, in fact - but it can get confusing, since I also (mis)use it to describe something good (“Wow, that’s genius.”)
Can’t go past a little P. G. Wodehouse!
I sometimes use “futhermucker,” but it becomes too easy to slip with that one and it’s too easy to figure out and to hear incorrectly.
“Fiddlesticks” works pretty well for me - and has the effect of being so silly that it can difuse tense situations that bring on swearing in the first place.
I can get away with “bloody 'ell” sometimes - as long as I’m not speaking to a Brit.
Beyond those, I pretty much just cuss like a sailor (no offense intended to any polite sailors out there.)
You trying to say that the Brits are more easily offended???
This Irish Brit uses the term “Bloody Nora” - from a 1970’s sit com!
I also swear in Italian - I was taught to do this a by an Italian Plumber - and those guys traditionaly swear each time they hit something with a hammer!
“Bugger me Backwards” is another favorite as is “Strap me Down and Sook me wang!”, sort of regional slang from the North East of England!
"KCaScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr " - this one laways makes me feel better and geberaly gets a few questions too!
Here’s some of the phrases I have been -trying- to use in place of swear words:
-“Fluck a flicka” (but my daughter always catches me on that one, telling me that it’s still a curse word–hehe, no it’s not, it’s got an l in it!) Oh, this one is one I just stumbled onto by … luck I guess. 
-“Sugar shack” I don’t know how I came across this one either, but it works well in place of the other well-known curse word. 
“Fishsticks!” Lifted from Filburt on Rocko’s Modern Life. I also use derivitives such as “Fish!” “Fish food!” “Fish feet!” and recently “Fish fat!”
“Doggit!” and “Dogs!” Both derivitives of “Doggone it!”
I’ll also spooneristically use “Chrisus Jeest!” every once in a while.
Ah, yes… and “Dumb it!”
Razzenfrats has always worked for me, as has Shucky-darn. Also ding-dong - as in “I can’t get the ding-dong jar opened!”
MOTHER OF GOD!!!
(with all the exclamation points)
“Dorfle-puddy!”
Comes from a play I did in High School called The Clumsy Custard Horror Show and Ice Cream Clone Review
I’ve been using “Son of a Bean” sometimes adding a “pole” to the end. I also use “frick”, “frack”, “gosh dernit” and “FRANK!!!” when I’m really “P’d off”. I don’t curse in front of the kids or one of my cow-orkers or out in public or on the phone with the parents. Frank me in the goat toushy, I almost never get to cuss.
I’ll swear in Japanese or use a phrase in Japanese. I lived there for two years and still remember the bad words.
Global Citizen
“Geez freakin’ louise!” (freakin’ is every third word out of my mouth sometimes)
“Phooey!”
“Ai Chihuahua!”
“Reffa steffa shneffa” (some cartoon dog – I don’t remember which one. Muttley, maybe?)
“Oof-tah” (some Scandanavian thing I picked up from a roommate from South Dakota) and
“God bless America” (though I don’t always remember to clench my teeth)
Forking polls.
Gore blimey! Great Caesar’s ghost! Jesus, Mary and Joseph in Tinsel Town!
Also, I’ve always wanted to call someone a foppish prickmedainty.
Ieasu Xristos. I have no clue where I picked it up, but it sounds cool.