I have only been on Mumsnet for a couple of days, but reading a few threads here leads me to believe that feminism needs an equivalent to Godwin's law, hopefully it would be another weapon in our armoury when faced with derailments on feminist issues.
A few triggers for this new law might be, for example:
Misandry.
Feminazi.
Hysterical women.
It happens to men too.
Porn's not bad because...
It's feminine empowerment.
Also what would we call it?