I haven't been party to that, yet! But I can imagine.
I think it would be easier for us to jot down the topics that have never (or at least, hardly ever if they're discussed alot) erupted into fights.
Yeah, we had one on here the other day about public breast-feeding. It was very entertaining, as I'm sure you can imagine! Certain topics seem to bring out the worst in us! lol Makes for a lot of fun.