People are Security Flaw of the Network

Today I grabbed some papers from the printer at work, looking for something I was waiting on. There were only papers for a co-worker, so I took them to her (as is customary at work). The first thing I saw when I looked to see if it was mine, is that the e-mail contained a username and password for a user on the corporate network. The user wasn't even one that seemed to be included in the e-mail. Even worse, it was a multi-recipient mail to many clerks from a supervisor. The SAs would have a damn fit if they saw that. No matter what security measurements they might take, people will still e-mail other people's passwords, which they shouldn't even have.