Put a stop to it
Sit back and watch it happen
Add to it
Some other option that I'm not considering
2) When do you consider it to be "out of hand"?
1) I'll generally sit back and watch it. I'll take sides in my head, but I usually don't say anything.
2) I don't really know--no drama in my posts (ok, post) has gotten that far--people usually lose interest in a day or two.