How 2 easily change workstations domain

Hi
We are currently going through a process to upgrade a windows NT 4 network to Windows 2000. We are upgrading equipment also so the new system will reside in parallel to the old until next weekend when we put the win2k system into production andremove NT4. What I would like to know is there a process I easily move the workstations to the new win2k domain without having to go to each one and join it manually. RIS is not really an option for us either. And unfortunately the pre-2000 domain name is different than the NT4 domain name also since they are both up and running on the same network. Have any good ideas?
Thanks
Pete