Educate Me - Netiquette

Let's talk netiquette. That's right the rules of boundaries and politeness on the internet. I hadn't really heard this term until I was approached to handle a small situation, no need for the details. The knowledge is more important.

Send me your thoughts and let's get a little knowledge passed around.

Examples:
Mr. Linky - some people post their urls twice and most likely this is an accident I'm sure, but is it really?
WW - Mr. Linky is used for us to share and blog hop around and see who is posting what. While I'm hopping around I found a spam within the carnival. Very annoying!
Is it ok to join as many carnivals as you can?

Posting a contest in your blog -
Some contests want you to spread the word about the contest and prize within your own blog. For one contest I cut and pasted the post and gave the author credit. I asked if this was ok after the fact but the author had no problem with it. For another contest I wanted to do the same cut and paste but they had a review of the prize. To be on the safe side I asked if this would be ok. The author said copy the contest and prize but not my review. No problem. When in doubt ask! Not sure what the proper netiquette would be other than asking. Why not just create a post of my very own? I have but sometimes I'm tired and my fingers hurt from typing and I want to go to sleep but then again I want to win the prize. lol