Jeff Atwood links to an online essay entitled “How to be a Programmer: A Short, Comprehensive, and Personal Summary” by Robert Read.
Robert's article tries to deal with all the stuff a programmer/developer might face in his/her job, from technical (“how to debug“) to personal (“how to deal with difficult people“) to career choices (“how to grow professionally“), and he does it well. He makes it clear that some of the topics he covers are going to be subjective and represent his opinion only, but knowing that from the outset helps and I reckon that's OK to look at his essay as “mentor-ish advice“.
I'm about half way through and am enjoying the bits on personal & inter-personal skills. Robert points out an important distinction between your company and your “tribe”, which is also interesting.