Code Review Etiquette
Another good one for the responsible coder. Code reviews are a tricky thing. They can improve software quality tremendously; two know more than one, obviously. However, it is all too easy to invoke bad feelings in the reviewee (if you think, "They should just grow thicker skin, it's not personal", this is especially for you). The simple fact of the matter is, coders are people too, and following some easy tips when doing reviews can go a long way to improve (or at least not reduce) the moral of the team and thus the code quality.