The GOnicus System Administrator (GOsa) is a GPL'ed PHP based administration tool for managing accounts and systems in LDAP databases provided by the GONICUS GmbH, Arnsberg, Germany. It administers users and groups, mail distribution lists, thin clients a
Penrose is a java-based virtual directory server. Virtual directory enables federating (aggregating) identity data from multiple heterogeneous sources like directory, databases, flat files, and web services - real-time - and makes it available to identity consumers via LDAP.
A popular thing to do with Samba these days is to join a Samba 3 host to a Windows Active Directory domain. You may freely set up any number of Samba servers in a Windows network without joining them to the domain. The advantages of domain membership are
S. Dietzold, and S. Auer. Proceedings of International Conference Semantics Systems 2007,
I-SEMANTICS'07, Graz, Austria; September 5 -- 7, 2007, page 290-296. Journal of Univeral Computer Science, (September 2007)