NSA Guide to Securing XP and securing your passwords
Tim Tabor referenced the NSA Guide to Securing XP in the Win Tech: Off Topic list. Craig Andera referenced Keith Brown's PasswordMinder project, a great utility for managing your passwords. Many people resort to using the same password for many systems, or they derive some pattern using the system in question (guilty!) for the password. The trouble with the former is obvious, the trouble with the latter less obvious; that is, until someone discerns the pattern.