How to deal with a Twitter troll - threaten to tell his mum

This. Is. Priceless.

There's been a lot of talk about Twitter trolls lately, and in particular how to best deal with the vile misogyny that many female commentators are subjected to.

As this exchange between Cambridge professor Mary Beard and one such upstanding example of the genre shows, sometimes the best thing to do is to threaten to bring in their mum.