Active Directory Mapping Tool

Does anyone know of a tool, utility or application that will not only enumerate an AD database, but display the tree objects (and their relationships to each other) in a graphical display, much like the HP OpenView AD snap-in does?

I am in the process of redesigning an AD – 2003 Server – environment and need a graphical representation of how everything looks from the root DC’s perspective downward.

This view includes ALL objects in the AD tree. any ideas?