In media where you assign an author to every piece of content, you can also filter by author. This helps you ignore other people’s FlameBait, and thus saves your aggravation. It requires, however, a certain amount of self-control, since you must decide to ignore fools and other people will still read them. Therefore, the fools can keep spreading their ideas, which might not be desirable. In fact, trolls can still poison the atmosphere of a newsgroup or an IRC channel even when many people ignore the troll. Newbies and occasional visitors will not be ignoring trolls and have to suffer.
TrustInPeople?! If you think that other people will be swayed by fools, take reasonable steps, but consider that other people are intelligent beings. You don’t have to follow fools around and counter every single argument they make. Put all your arguments somewhere else and point people to it.
This is often used on UseNet. Whenever a notorious troll posts, somebody else will post a pointer to an inofficial FAQ about the troll. Newsreaders also invented the term killfile to designate the file where you keep all authors you want to ignore. In order to ignore follow-ups to trolls, some newsreaders allow you to ignore threads started in reply to trolls.
On InternetRelayChat (IRC), you can either ignore individual nicks, or people with the necessary AccessLevel? can ban nicks from a channel. On IRC, tradition demands that you prefix public messages addressed to individual nicks with the nick (“kensanata: Try #perl instead”). Therefore, you can ignore messages addressed to trolls as long as they follow this convention. With some heuristics, you can even try to ignore follow-up messages by the same author in small time-windows, but it gets ever trickier to do right. See IgnoreList for more thoughts on the IRC aspect.
Ignoring has often been replaced by scoring or rating.
In places where there is central control, BanningUsers is also often used.
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