Have you ever been in an argument where you absolutely objectively proved you were correct?

Yes. My company wanted me to get a corporate credit card with Bank of America. I said absolutely not, they have a terrible reputation and I want nothing to do with them. In response, I was told in an email (which was Cc-ed to some VP of Finance) that this wasn't true, and that Bank of America has a great reputation.

Now, if you're gonna claim I'm wrong and start cc-ing people, you better be able to back it up. This pissed me off, so I googled for lists of the worst banks in America. Of the three first surveys on the topic that I found, two of them had Bank of America as the "top spot" as worst bank, and the third one had it in third place. I emailed this back to the person. I never heard back. I happily continued not using their corporate credit card ever after.