I used the term "saatana", which translates to "satan", by the way. Of course, since I was only three or four when I heard it from my grandfather, I pronounced it rather adorably. I didn't mean anything by it, I just repeated it since I figured it was a popular phrase.
On a related note, occasionally my grandfather was aware I was listening, and instead translated his swears in a humorous fashion. Despite being a finn, he'd exclaim "Satan's namn på svenska", in those exact words. Any swedes on the boards may find this giggle-worthy.
I actually have a habit of swearing like a sailor, but I'll suddenly become well mannered should my mother be present. She raised us not to fear God, but to fear her wrath. To this day, I get chills whenever I catch myself sweating in her presence. She doesn't seem to care, probably just happy she raised us proper. =/