We have a couple of "codes" we use after discussing them with DD. One of them is "wall". I'm not even completely sure of the logic behind it anymore, but I think it was that she becomes so engrossed in the battle she forgets why she's arguing and crashes into the wall... I think. Or maybe it's because I've been known to make her stand with her nose on the wall when she engages in a battle of wills while I'm tutoring someone else. Anyhow. She usually stops.
The other is "stop spending my dimes." When she was very young I gave her 10 dimes and every time she argued I took a time. I explained that I only had so many dimes to spend a day myself, and when I ran out, I didn't have any energy left to "spend" doing fun stuff with her. Somehow that seemed concrete.
At 9, she does better with the controlled choices others have described above. When she used a "bad" word (picked up from my mother, long story), she began full scale battle against a 10 minute time out. So I said, "what would be appropriate". She decided to come up with 25 written alternatives to the word she'd used. She looked them up, wrote them neatly and said, "that was interesting."
I did read (for me) 10 Days to Less Defiant Child, which was about 60% relevant and mostly about how to phrase things so as to not escalate a situation.
good luck.
