YubiKey provides an extra layer of security for logging in to your password manager service to ensure that no one else can access to your list of unique passwords.
LastPass is a browser-based password manager that specializes in making web browsing easier and more secure across multiple platforms.
Passpack is a web-based password manager that offers additional password management features such as password sharing.
KeePass is an open source PC based password manager primarily for Windows users. It offers many features and is targeted at advanced users.