Do you have a lot of passwords? Are they too hard to remember? Then use a secure password storage database. Password Safe, Password Gorilla, xPass, and several other tools are available. They all remember your user names, passwords, URLs, etc, and store them all in a strongly-encrypted database.
You should protect this database with a VERY LONG passphrase. Then you only need to remember this passphrase and your computer’s password to have full access to all of your passwords—passwords which are now securely stored.