I weirdly don't get nearly as much hate mail as I did years ago (hate communications generally). I do occasionally get a bit. Roughly I can divide them into 2 categories. The first involves people getting really really angry about things that I would have thought would be the least anger-inducing. That's what set you off? Really? OK I guess. I'm not going to tell you what to get mad about, but that?
The second is people who send me The Truth, deep bits of wisdom and knowledge that only they have access to and which couldn't have possibly occurred to me before. Some of these people are very interesting, and if they had newsletters I would surely subscribe to them. I might even read their blogs!