Where have you encountered people who spew off at the mouth?

Me. I admit it, I do that. Of course, I only butt in when I have knowledge about something, but I haven't yet learned to stay out where my nose doesn't belong. For some reason I still have the "I can't let you go through life with such a horrible misunderstanding of the way things are" attitude, when really it isn't going to make much of a difference and they aren't going to appreciate the input anyway. My wife gets on to me constantly about this too. Oh well, no one's perfect.

As I said, though, at least when I butt in I do it with knowledge. I know how to keep my mouth shut when I'm ignorant of something. The worst is sales people though, and I'm never sure what to do with them. Like the Comp USA guy who was bragging to me about his dual processor windows 98 machine while trying to sell my wife a laptop.