Hard Passwords Made Easy
http://www.freesoftwaremagazine.com/free_issues/issue_02/hard_passwords/

Locke, John
Free Software Magazine
2005

Abstract:

In this article, I’ll discuss how to create a strong password, and how to keep track of all your strong passwords, if you have a definite need to keep more than a couple. Don't bother creating and remembering strong passwords for low value systems, and certainly don’t use the same passwords for low value systems that you use in high value systems.