Slashdot comments could never go below -1 (or above +5). Also, moderation wasn't an "everyone votes" thing, moderators were picked semi-randomly and if you got picked, you could only place 5 votes. If you voted and the posted a comment on the same topic all of your moderations would go away.

There was also Meta Moderation where you'd randomly get shown a handful of comments and votes on those comments and you would be asked to judge whether the votes were fair or not. Supposedly those votes would affect your likelihood to get tapped for moderation again.

It would only show one adjective, but the ordering was kind of funny. If someone moderates your comment as a troll but enough people marked it with positive votes, you'd get the coveted "+5 Troll" badge.