Chad Dickerson at Infoworld has an article on the top 20 I.T. mistakes to avoid.
Overview from the website:
We all like to think we learn from mistakes, whether our own or others’. So in theory, the more serious bloopers you know about, the less likely you are to be under the bright light of interrogation, explaining how you managed to screw up big-time. That’s why we put out an all-points bulletin to IT managers and vendors everywhere: For the good of humanity, tell us about the gotchas that have gotten you, so others can avoid them.