Q: Is there a free enterprise-caliber password-management tool for end users?
A: Two come to mind; Password Safe is an open source product that encrypts user names and passwords in one or more databases and allows the company to manage those passwords based on policies it controls.
The second is KeePass. This product has a freeware version that also encrypts passwords, and an enterprise version is available for purchase that allows central administration of passwords.
Both have established followings of thousands of users, they are free and offer safe and convenient password management. Keep in mind that none of these freeware applications have the features required to roll out to the enterprise and centrally administer by policy or rule sets. You are dependent on end users to manage the application themselves, creating a thousand points of potential failure, but the benefits of some password security still make it a better alternative to nothing. At a minimum, there should be fewer sticky notes with passwords on desks.