KDE remote desktop

http://docs.kde.org/development/en/kdenetwork/krdc/using-krdc.html

To send an invitation, use krfb at the prompt. Create an invitation and save the node name and password.

Type in kdrc at a shell prompt to connect to the invitation.
Use vnc:/nodename:0
You will be asked to authenticate which the originator must do.
Then you will have to type in the password (which the originator noted down from krfb)