Your mention of seven years of your inbox, together with your calling this "fairly mild", makes me wonder: does any archive exist where someone has posted a large volume of the offensive mail they get, just to give an idea of both scale and magnitude? I'm starting to get the impression that I have no concept of just how serious this problem is, and I already thought it was extremely serious.

I also wonder: if you've received non-generalized threats of violence, have you ever attempted to report them? I realize that this seems about as likely to succeed as trying to eliminate sources of spam, but just as it's always satisfying to read about a major spam hub getting shut down, it would be equally satisfying to read about someone sending such offensive garbage getting arrested for it.