It's been some time since my experiments with OpenLDAP... Now at ONLamp.com, I found Dustin Puryear's nice "getting started with LDAP" article:

"There has been a lot of buzz in the past few years about using the Lightweight Directory Access Protocol (LDAP) for centralizing system and network information, providing cross-platform user account databases, and even for creating a single repository of printer definitions and configuration information. All of these uses are truly incredible, and they only go to show you the level of flexibility available with LDAP. Most of these examples neglect an important and obvious example--using LDAP for a company-wide address book."