Michael Moore is the closest I could come up with. What makes Coulter unique is that she actively tries to offend liberals. I can't really think of anyone famous for trying to offend conservatives (although lots of people have become "almost famous" that way.)
I happen to think both sometimes make useful and thought-provoking points, though followup conversations about them are prone to derailment into all sorts of superficial reactions and over-rehearsed ideological set-pieces.
The problem is that these people create true believers. The world could really use sane alternate viewpoints -- and we mainly get lots of conspiracy theorists unable to change viewpoints.
That is also more than I care to know; the US extreme left/right looks equally insane. I just wish neither was popular here. But I guess you get the good with the bad.
I agreed with a quote as a way of saying that they generate hypotheses that probably aren't correct, but potentially fruitful to work from.
Seriously, tho', Chomsky? Would an Ann Coulter diatribe last as long?