I just checked and have seven blocked. I know I answered Red_Arrow with four but I just briefly glanced. The weird thing is where there were two there is a blank space and I know they were female users, so I have to wonder if they deleted their accounts since I blocked them.
I've said it before, I block when someone becomes insulting toward me. Even if I point something out and get the childish, "You should go back to school." I'll give the person a chance to just go back to normal, but if they can't do it, I block. I'm not wasting my time online to sit and read someone who has no significance in my life to make attempts to make me feel bad. And that's what they try to do - attempt. Not that it works, it doesn't. I just hate the fact I'm talking to someone who *tries* to be hurtful.
Anyway, I did most of my blocking when I got tangled up in most of the feminism discussions because there are a lot of people who simply don't know how to discuss. They give me nothing to take away, and have a refusal to even read what I write because a lot of them come back with crap that I already covered, proving they just are spouting off their hate toward something without even reading someone's information. If they don't read what I say, in a small box of 1000 words, then they're not reading articles, statistics, news stories - nothing. It's just based on personal experience or empirical evidence - all subjective.
I also have some right-wing-nutty people who become loose cannons when it comes to religion and abortion. I can only take so much bigotry before I decide it's evident that there could be a bigger issue going on with them besides religion, and talking to a brick wall is stupid. So in every topic, they're the same one-note tune and come to my questions with the same bigotry - I like to save the GaG community from having to be exposed to it.
So there you go, seven at the moment, and they probably know who they are. :) It's too bad because I'm sure when it came to other topics, we'd be in agreement with and probably upvote each other, but GaG has no notification turn-offs, so the only solution to shut the person up who is causing trouble in one question or myTake of mine is to just block.