In the past I posted about how to create strong passwords (and passphrases) in six easy steps. Here's more info from PC World on MSN Tech & Gadgets on how to "protect your privacy and your data with strong passwords--plus some ideas for tormenting squirrels."
(Please note I have no involvement with the squirrel reference.)
Here are a few of the author's suggestions for creating passwords for web sites... and even one for storing all your user ID and password data:
WinGuides' Web-based tool that helps you create good passwords.
Also see Steve Gibson's Perfect Passwords.
And RoboForm - this program also remembers the passwords for you and has a handy connection to a Pass2Go USB key for keeping your passowords available.
Some of the best web sites will ask if you want to update and change your password regularly - I wish more presented this as an option. Some regularly change their on-line access navigation, the series of pages you have to go through to access your account or recover a password or account information (as we recently found out when accessing a bank site today).
Whatever you do, change your passwords regularly and make them strong!
As they said on Hill Street Blues: "Remember... let's be careful out there." (Gee, I'm showing my age...)