Here is an interesting take on how to optimize the strength of your passwords.
XKCD created this web comic based on this paper (PDF) about best practices for creating passwords. It is pretty different than the common accepted approach to creating a secure code, and would be much easier for most people to remember.
Take a look:
This was reblogged from boingboing.net where there is an interesting discussion going on about the legitimacy and difficulties of using this system.