KeePass is a password manager. It stores many passwords which are unlocked by one master password. The idea is to only have to remember one high-quality password, and still be able to use unique passwords for various accounts. It has a feature to automatically fill in passwords in web forms.
For downloads and more information,
visit the KeePass homepage.
I love this program. I used it to create a password file which I then sync between my desktop, laptop and Android phone using sugarsync. Yes there are password managers that store the database in the cloud for you, but what happens when you don't have internet access? This way I get the best of both worlds.