Eviscerate them in fiction. This is the preferred choice ever since a popular Archean female singing trio dismissed the Iliad as a trite war story and ended up being depicted as murderous women headed birds. Try to keep it in proportion though; Micheal Creighton portrayed one of his critics as a child rapist with a tiny penis which is overkill, everybody knows that on the sliding scale of fictional evisceration a bad review merits a horrible death (real or social depending on genre) - they'd have to be something personal involved to get me up to Creightonian levels.
So remember my fellow writers: kill em in fiction, is cheaper, less likely to get you arrested and almost as much fun as the real thing.(1)
(1) If it isn't you are not a writer but a psychopath please report to your local mental health institution and turn yourself in.