I only have one password that I even know. That one password I use to get into KeePass, and that is where I keep all my other passwords. I use random characters, and use the additional entropy, and I use the longest password with the most varied characters possible. And to top it all off I keep the whole thing on a thumbdrive that I keep with me. The one password that I use has over 20 characters, and it is a non word, and it is paired with a random 256 character key just to open my password database. But to really confuse the issue, I have several other files that are the same size and type as my key. If anyone does get into my password file, they will have earned whatever they find.
I have not found anything yet that does a better job of keeping my passwords safe and secure. The best part, KeePass is free. http://keepass.info/