The best troll accusation I ever suffered was some extended exegesis on my user name, something along the lines of "You might think it's a 'mystery,' alcibiades_mystery, but me and many others here know what you're up to; we know all about Alcibiades and your mystery has been solved!"

It contained all the classic signs of troll-accusation:

1) The "Half" Accusation - Rarely do the Accusers ever come out and say "Troll!" Rather, they imply that you're up to some nefarious purposes, primarily because they know an outright accusation of trollery is against the rules. Needless to say, this is so cowardly and half-assed that anyone with a shred of dignity can hardly stand it. It has all the subtlety of the street-corner commissar tipping off the secret police to a possible enemy of the state by sly pointing. It's clownish, and people on this site who do it should be ridiculed for it.

2) The "Me-And-All-My-Friends" Gambit - It's amazing to me that grown adults still continue with this junior high school bullshit. In almost every half-accusation of trollery there is some gesture towards the many others who also think so. This is pure, junior high school mean girl rhetoric, and unworthy of decent discourse. Not only don't I like you, it says, but nobody else likes you either. How anyone over the age of twelve could take such nonsense seriously is a mystery indeed. But these folks not only take it seriously; they actually deploy this juvenile rhetoric in public! It's quite shocking that adults conduct themselves in this way.

3) The "We're Watching You" Strategy - In almost any accusation of trollery, there is the implication that you have been surveilled for quite some time. "We've been looking at your posts, see. They are in the - ahem - dossier. You're on file. You've been noted in the building." The extent to which people love and cherish deeply their little fascist tendencies is mostly amusing, but often scary as well.

These are the characteristics of the "troll accusation genre" that I've noticed. Any others?