One problem people struggle with is keeping eDirectory group membership information in sync. eDirectory stores Groups as double-linked lists. What this means is, the Group has a pointer to the User and the User has a pointer to the Group. The problem is, when you use LDAP to update the User, eDirectory does not automatically update the Group and vice versa.
This driver is based on the NDS2NDS driver but it actually talks directly to itself, rather than to another tree. When you modify the Group and point it to a User, this driver automatically updates the User to point to the Group. When you update the User to point to the Group, this driver automatically updates the Group to point to the User.
There are surely other applications for this approach. Maybe this driver will give readers a start on solutions of their own.