27. Don't try to extend a conversation beyond pleasantries (e.g. can you please pass this to the flight attendant, excuse me, I need to pass you to go to the lav, etc.) to include your life story that just goes on and on and on. The person you are trying to engage is really more interested in their book, their computer game, the movie, the magazines/newspapers or just plain shuteye than being your rapt audience for the remainder of the flight. Please respect their personal space and wishes, especially if they start dropping cues that they don't want to talk to you!

I know there are exceptions to this one, e.g.:

When you are single and there is a hot guy (used to be my case, now I'm married ) or a hot chick who is just hanging on to your everyword.

You happen to find out a good networking prospect.

These cases are the minority, tho. I'm sure most of you have already visualized the scenario I listed as 27.