"I swanny."
I was just thinking of this earlier. It really takes a swear-averse culture to use a euphemism for "I swear."
In the last 10 years, my mother has started saying "bitch" tentatively, when the person being described is one. I've never heard her swear. She slams things instead.
My mom says "Oh, ick," which is a very 1940's teenager way to not-swear.
A few weeks ago when my family and I were locked out of my parent's van after dinner, Mom yelled "SHIT!" in front of the restaurant entrance, which is absolutely hilarious considering how much of a goody two-shoes she is. Much of my own annoyance at the situation disappeared as a result.
When I told my mom I had a boyfriend (after almost a decade of being a total lezzie, as far as she knew), she exclaimed, "holy SHIT!!" Which sent my sister and me into gales of laughter, and then she chided herself for cursing on the Sabbath, which just made us laugh more.
I said "Oh my god," once, and my mother nearly drove off the road, she was so busy telling me how horrified and disappointed she was in me.
I often say Holy Mother of God, or Mother of God when I really want to say Motherfucker.
I do this except it usually backfires and I wind up saying Holy Mother of FUCK.
Grandma E says "oh foot!" that's the strongest thing I've heard from her ever.
I say "Jesus H Baldheaded Christ!" sometimes. When the situation demands it.
I'm waiting for the opportnity to use "Jesus, Mary, and Jenna Jameson!" in response to someone.