More types of flagging? 
wglb: I would favor the addition of a rude/inappropriate/trollish vote that would be anonymous in addition to the current upvote/downvote.  Perhaps those are three buttons that are downvotes in that category.This would add a useful dimension to the feedback.I find myself using the up/down arrow largely for "contributes to the discussion".  There is an element of "I agree", but I frequently click up on a comment that I disagree with because it is well-reasoned or brings up a thoughtful angle that is new.To avoid the mob clicking of these new buttons, they could be shown only to the author of the comment, or very high karma individuals.