"I can't remember the last day where I opened my email and there wasn't a piece of vicious (often sexual, often violent) hate mail there. I also don't write about it because these days I'm loath to give any attention to harassers - in part because that's what they're so desperate for, but also because the threats have become so bad that my life offline has been seriously impaired by it and I'm just plain scared. But that's the goal of harassers - to scare, to terrorise, but most of all, to shut us up."

In Australia, social commentator Nina Funnell, newsreader Jacinta Tynan and anti-porn campaigner Melinda Tankard Reist have also spoken out recently about the vicious sexual trolling they receive by email, Facebook and Twitter on a daily basis.

In an analysis of the responses to a blog post about rape culture, Boston-based blogger Courtney Stanton found that one in four of the more than 400 responses she received was from trolls looking to inflame the debate with aggressive pro-rape posts.

Most of the trolls hoped Stanton or her mother or her daughter would be raped and/or killed, while many also called her fat and ugly and "too repulsive to be raped".

While most of the trolls were from North America, several came from Australia, Britain and Europe and a few from South America.