As a security person, I cannot bring myself to endorse writing down passwords, although it is probably better than having an obvious password (security people know how to check drawers and under keyboards).

FORBES: Discussing Gawker's Breach With Founder Nick Denton

Also, it doesn't hurt to check your account balance annually, by phoning an automated or recorded line or logging into a password-protected online account.

WSJ: State Governments Eye 'Inactive' Broker Accounts