There's always pcAnywhere...it can get expensive fast.
Also see
http://www.tridiavnc.com/, I have not yet tried this solution.
>Hi. I have a NT server with a Win 2000 Terminal Server. In the past, I had seen some software that allows the administrator/programmer to see the other user's screen (when they needed help). Does anyone know of such a product?
>
>R
Steve Gibson