Pretty simple:
No racism.
No thrashing of people's religion.
No selling things without paying the pimp. (That would be perkiset)
No links in posts.
*** Exception: Talk to me about them and they might be ok, given context etc.
No links in signatures.
No spam.
If you must flame, be reasonable about it. Don't be an ass.
If you are a n00b, be respectful. The people here have WAY TOO MUCH experience to put up with your shit.
If you post your own URL here please realize that it will get picked up by spiders and read by people that you may not want reading it.
There are a lot of black hats here. There are a lot of people that might take advantage of you. Don't be naive.
NEVER NEVER NEVER post someone else's URL unless you want to get flamed, smacked around or even banned.

Did I mention that you must NEVER NEVER NEVER post someone else's URL here? Good.
/p