Be careful who you tick off...

Do not meddle in the affairs of System Administrators, for they are quick to anger, and have no need of subtlety. This guy got a bad performance review, and they tried to fire him, but it didn't work. His revenge? He disabled everyone's login but his own, to the entire San Fransisco city network. City e-mail, payroll, police documents, etc. are all inaccessible while this guy sits in jail refusing to give up his password. Full story here.