There's also a persistent rumor/concept among Linux aficionados that some or all of the worst profanity spouting, knuckle-dragging, "Sodomize Microsoft!" fanbois are actually paid-for "reverse shills". That is, some vague conspiracy finances trolls to make the rest of Linux advocates look stupid. This rumor seems like an example of "Poe's Law" (http://en.wikipedia.org/wiki/Poes_law) in action.
I'm reminded of the recent HBGary hack/infodump which contained a lot of material about creating software to ease/simplify sockpuppeting and plausible background generation for the US government.
