I love the word "fuck". I loved the scene in The Wire (love The Wire) when cops went into the crime scene house and did their investigative thing only saying "fuck" with a variety of meanings. Such a useful word!
I say "oh god" or "goddamn it" on occasion and I do think that its a little strange that I use it. I think its because its so ingrained into me I just can't shake it. My mother in law says "dogs" often when she wants to curse.
Depends on situation. If it's nothing big I'll say "hell" or "damn", this escalates to "shit" "fuck" "piss" ect ect. If I'm really really pissed I'll yell something like "piss shit bitch!" or my personal favorite "Great Jupiter's COCK!".
One year I gave my biology classes an assignment to create a mnemonic (exam: “King Phillip Came Over For Good Spaghetti” = Kingdom, Phylum, Class, Order, Family, Genus, Species) for the major nerves, the major bones, major blood vessels, the endocrine glands, etc. The only restriction was they could only use words that appear in their biology text – bad mistake.
One would be surprised at how down right obscene a high school junior can be using only biological terminology. 80% of the mnemonics for the Vegas Nerve was Vagina, the Pituitary was predominately Penis and the Clavicle was Clitoris, Renal Artery = Rectum, Aorta = anus - you get the picture.
The second mistake was that they were to be voted on and were, therefore, printed out on large poster size paper and displayed around the room.
Fortunately, no parent or administrator showed up during my 5 biology classes. The students were, however, extremely creative.
I decided that I wouldn't repeat the exercise the following year.