These days almost everything online requires a password. You already know that you should use complicated passwords and that you shouldn't use the same password for every account. Here are more tips on how to create stronger passwords and how to test your password strength.
If you want to know why it's so important to create different strong passwords for all of your accounts (and to change them often), see How I'd hack your passwords by MSN Money blogger, John Pozadzides.
This article and its links are well done to explain why we must add at least a little effort in security.
But even if most people are aware about all the problem behind, i think it could be a good idea to provide a way to manage all this passwords. Because, simply speaking, nobody want to spend time to remember what is the right password for this application or this website, especially if it is frequently changed.
Of Course, the answer can't be: write it on a note and put it under your keyboard ...
So, any good answer to that could really help to provide the right attitude about security as advised.