I like the default HN approach (Slashdot used to do this too): users can upvote/downvote, and by default you don't see content that's downvoted far enough, but if you want to see everything, you have the option. That seems to work well enough against spammers.
That's the same as reddit's system. HN hasn't fallen into the pit of lowest common denominator jokes is the strong moderation, but the system still has inherent issues with high-quality posts losing visibility because they're less appealing.
Well, no, reddit "supplements" it by banning pretty much every forum whose regulars don't match the owner's political ideology. There's no "uncheck this box to see all the stuff I didn't like" option there. I remember Reddit before they got ban-happy, and it was a much friendlier place then - and actually less overtaken by extremists.
