1. Be polite and respectful by default. A House Rule, but worth restating.
2. Get into the habit of previewing your posts. This enables you to correct any silly mistakes and reconsider whether you really want to say that.
3. Control the urge to correct others' mistakes. Except in places like Peer Review, people rarely appreciate it.
4. Be careful about revealing personal information in the forums - undesirables may use it as ammunition.
5. If someone starts having a go at you out of the blue, act defensively. Be factual, point out holes in their arguments, but don't sink to their level.
6. If they really hit a raw nerve, rein yourself in. Don't fly off the handle - unsubscribing is far less painful than a flame war.
7. If seriously inebriated, don't post. You'll only regret it in the morning.
8. If you're not sure whether or not to post in a conversation you feel morally dubious about, *don't* post.
9. Try to ignore postings by people you know you don't like. This will save endless aggravation.
10. Stick to what you know or can extrapolate to. There are plenty of well-informed researchers here and guesswork will have you floundering in no time.
11. Don't be upset if people don't answer your posts as soon as you'd like. They may be really busy, in bed with flu, emigrating...
12. Expect threads to change their topic, often to something quite unrelated. This phenomenon is known as topic drift.
13. Use Smileys to increase the clarity of your meaning, or just to be sociable.
14. The best debating technique is not to attack your opponent's weakest points. Try attacking their strongest ones - if you can beat them, you're unassailable.