ActiveXperts Network Monitor proactively manages network servers, devices, databases and more.

Microsoft Resource Kits - Windows NT4 Resource Kit

Findgrp.exe  (Windows NT4 Resource Kit)

The Window Server NT4 Resource Kit is a set of tools that NT domain administrators and engineers use to manage or support a Windows NT4 domain. Use it to streamline management tasks such as troubleshooting NT4 OS issues, managing an NT4 domain, and configuring networking/application services.
Findgrp.exe
Finds all local and global group memberships for a user in both an accounts domain and a resource domain.