NT Authentication using jCIFS Filter
I became aware of the jCIFS (Java Common Internet File System) project today (via the tomcat-user mailing list).
The Common Internet File System (CIFS) is the de-facto standard file sharing protocol on the Microsoft Windows platform. It is the underlying networking protocol used when accessing "shares" with Windows Explorer, the Network Neighborhood, via a Map Network Drive... dialog, the C:\> net use * \\server\share commands, or smbclient on UNIX, smbfs on Linux, and elsewhere.
What's cool about this project is you can use a filter it provides to do NT Domain Authentication. Unlike the JAAS module I've covered before, this one doesn't require Windows and it also supports auto-login for Internet Explorer. This sounds like a great project if you have an NT Domain you need to talk to for authentication.