This shows how to use Windows Remote Desktop v5 over SSH over the Internet. It helps if you're running Linux, SSHing to another Linux machine and then forwarding an RDP connection to a Windows box.
Set up your initial tunnel from your own Linux box to another remote one on the Windows network:
ssh -C -L3389:localhost:3389 user@remotelinuxmachine
The set up your port forward for RDP to the Windows box:
ssh -L 3389:192.168.0.114:3389 localhost
Now run your RDP client and point it at localhost.