I'm sure we've all seen these on our BB before. :chuckle
1. Tell your opponent that the argument is over, because it's degenerated into pointlessness.... doing so at the end of your post giving you the lengthy last word in it.
2. Predict the imminent death of the Internet.
3. Call your opponent a Nazi.
4. Change the subject by pointing out all of your opponent's grammar
5. Post some horribly vicious and insulting note about your opponent.... several minutes later, post a profuse apology, claiming that you'd intended to send the message privately to a friend.
6. a: Refer frequently to pretend hordes of lurking supporters, who have mailed you privately to express their agreement and gratitude.... but aren't willing to come out publicly and say anything. (See also here.)
6b: Accuse your opponent of trying to intimidate your hordes of supporters.... add indignantly that you "will not be silenced".
7. Attempt to impress/silence your opponent by discussing your professional credentials and experience related to the topic at hand, which clearly make your opinions better and more correct than anyone else's.... be vague about details if your credentials and experience aren't actually all that impressive. (Also known as "dueling resumes".)
8. Accuse your opponent of being overly sensitive, or suggest in a patronizing tone that they "must be having a bad day".
9. Claim that an insult or other rudeness was "just a joke", and suggest that your opponent has no sense of humor.
10. Claim that *everything* is a matter of opinion, that there are no such things as facts or truth.
11. a: Claim that facts are absolute.... that there's never any such thing as dispute or disagreement about a fact.
11b: Assume that everything you learned in college, no matter how many years ago nor how much a field has advanced in the meantime, is completely unchanged.
12. Redefine words to mean whatever you want them to mean. (Also known as the "Humpty Dumpty" defense.)
13. Refuse to look something up, if challenged to do so.... no need, surely your memory is perfect.
14. Ask your opponent to supply lengthy and detailed references for their every statement.
15. Claim that if something works for you/your spouse/your kid/your parent/your best friend/your boss/your hairdresser's first cousin's dog's veterinarian, it will always work for everyone.... and if it doesn't, it's because they're not doing it right.