Went back and looked up the last conversations I had with these people. Here are the basic reasons I chose not to deal with them any longer. I know there was more to it, but this is the gist of what caused me to hit the Twit button:

Denis Chasse: Inane passive-aggressive comments. Just got tired of the insults dressed up in childish wit.
Evan Delay: Extreme liberal views bothered me at first. The anit-USA condescending attitute clinched it.
Jean Laeremans: Just got tired of his attitude. Always attacking and being smug about it.
Chris McCandless: Incredibly condescending and insulting.
Naomi Nosonovsky: Weary of trying to communicate with her. She is never wrong. It's always someone else's fault.
John Ryan: I can't really tell why. We disagreed a lot, but didn't see anything too heavy.
Terry Thurber: Oh my God. I can't even begin on this guy. Or girl, I never really knew. What a shmuck.
Peter De Valença: Very tiring to read. Same thin arguments over and over. The Great Thin-Skinned White Knight.

I was actually surprised at some people who are not on my list.

Ok, bring mine on. I'm sure I'm on a filter or two. If I can dish it out, then I better be able to take it too. Oh, wait. Those people aren't reading this anyway.