I'm actually permbanned from an IRC network I used for quite literally less than five minutes. Someone asked a question in a channel, and I knew the answer. Thanks to lag, I answered about simultaneously with an IRCop. We had different answers. He informed the channel I was wrong, but I had included a link in case anyone wanted more information.

When everyone said, "Um, actually, the people who make the equipment and posted the reference manual he just linked seem to agree with him..."

And off I go, with "People who make me look bad aren't welcome here" as the kill message. He actually banned my entire state on that ISP -- and the ban's still there five years later. (Along with like five users on a good day, from what I'm told.)