NoNameProf

this is something related to game theory, but variations of it have been successfully practiced by many people, myself included. I really can not claim credit to it, but here are the ideas:

1. be nice to people (and make the effort to show them you are nice)
2. if others are not nice to you, then try to make them worse off (i.e., be vengeful)
3. be willing to forgive people if they show they regret their (not so nice) action (but not just in words, insist they should do things to make up to you)

the important thing here is that you need to establish the reputation above, then you do not have to worry about actually enforcing it (second and third rules). also, you should tell others about these rules, and avoid making it personal (simply state this is how I treat everybody).