From Skepchick, here is Rebecca Watson describing some of the vile, misogynist invective that has been leveled at her since she posted about "elevatorgate":
If you aren't familiar with the story, well, do some hunting at skepchick and you'll find it. Suffice it to say that a lot of men do not like to be called to task for patriarchal attitudes. Only instead of reasoned and rational response, they throw around words like cunt and bitch.
Which is the point. We're all free to agree or disagree with Rebecca, but when you start hurling epithets because you've exhausted your vocabulary of non-four-letter words, then you're just an asshat.