I really like Terminal Services not only on application servers but also for remote administration and for remote access to client desktops running Windows XP. I'm not sure of how secure you want the connection to be. The degree of security is set on the server under Terminal Services configuration. If you're considering using RDP from outside to reach into the enterprise, RDP does not currently support SSL, but does work with VPNs. You don't need a certificate server for RDP to use terminal services.
This was first published in April 2004