In reply to Please Read: Typophile (TEMP):
> Could a user based spam report system work?
This, damn it. Exactly this.
1. Add a "spam" flag to every post/comment, and let anyone with a post count over 100 use it.
2. Add an option to user's preferences to hide comments that are flagged as "spam" more than, say, 5 times. Turn this option on by default.
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3. Instead of flagged/clean, let a post/comment to have 3 states - clean, possible spam, spam - with 0, 1-4 and 5+ flags respectively. When a comment is in a "possible spam" range, show it, but gray out. Also, show a "not spam" flag, so to allow undoing accidental or mischievous flagging.
4. Revoke flagging rights for those whose flagging collects too many "not spam" reversals.
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1 and 2 are trivial to do, perhaps 2 hours of works if that much.
3 and 4 are more work, but that's why they are bonus.