Chomsky has some capacity for substanceless ad hominem, and it's only ever pulled out for those for whom he has zero respect but who are also allies. He just couches it in an aww shucks, who me routine so you don't really notice it.
As for biliousness, the feminist blogosphere once had this big discussion about biliousness. The question was about rhetorical tactics and I think it was something Katha Pollit wrote, or maybe Amanda Marcotte. In any event, both Katha and Amanda, as well as others such as Twisty Faster and Jessica Valenti, were seen as really funny and hilarious when they twist the balls of an agreed-on enemy. People said that it was really hilarious when freminist writers were vicious to a shared enemy. To them, it was cathartic to read it. They felt that, when it came to the enemy, they didn't care if same feminists were not just vicious but it was fine to use use unethical debate tactics (logical fallacy) as long as it was in the service of slaying a common foe.
But there was an opposition who thought it wasn't such a good idea to cheer that sort of thing on. They wondered what such cheering said about the people sitting on the sidelines, reading viciousness and enjoying it. Is it a good thing to engage in mocking, ridicule, viciousness, personal attacks on people's appearance, their families, etc. - all in the name of the claim that "All's fair in war?"
Katha Pollitt participated in this discussion for awhile, on the old blog, IIRC.
It's a tough question. I can see the merit of argument on both sides.
What was most interesting to me, and something I'd never considered until then, is that some folks admitted that, while they love to watch bloggers eviscerate others, they were also terrified of the blogger. They laugh and admire them, of course, but several people in that debate spoke about how they are also fearful. It's why they would hardly ever get into disagreements with vicious bloggers. They felt that, if they did, they risked the person attacking them with the same vicious approach.
The question then came up as to whether people who were consistently vicious like this weren't actually just exercising a form of domination, much as Weber argued that nation states do: they wage war on third world countries to let the citizenry at home know who is boss.
For at least one faction of the audience, they felt that such behavior had a chilling effect on conversation. It ended up leading some feminist bloggers to change their approach because they hadn't realized that they were hindering debate on their own blogs.