The recent implementation of a -5 karma penalty for replying to comments that are at -3 or below has clearly met with some disagreement and controversy. See http://lesswrong.com/r/discussion/lw/eb9/meta_karma_for_last_30_days/7aon . However, at the same time, it seems that Eliezer's observation that trolling and related problems have over time gotten worse here may be correct. It may be that this an inevitable consequence of growth, but it may be that it can be handled or reduced with some solution or set of solutions. I'm starting this discussion thread for people to propose possible solutions. To minimize anchoring bias and related problems, I'm not going to include my ideas in this header but in a comment below. People should think about the problem before reading proposed solutions (again to minimize anchoring issues).
I think we need to have a better way to separate true trolls (an admittedly loose category) from people who can be reasoned with and/or raise interesting points but are being down voted for other reasons (like poor grammar/writing). Once we have this we need to convince people to stop feeding the trolls. One way that I have seen proposed is tagged karma (eg +1 insightful -1 trolling). Additionally sockpuppets haven't been a major problem here, but given the role they tend to play in website decline we should have a strategy for dealing with them in advance.