While I finally managed to set up a dual seat Kubuntu desktop (see my answer on askubuntu.com for how I did with two nvidia cards using the native drivers), I'm somehow stuck with an apparently simple problem: I want to be able to share the screen of one seat with the other and can't figure out how to do it.
Occasionally, the user of seat0 wants to share something that is on her screen with the user of seat1 (could also be the other way round, so I'm looking for a two-way solution). The seat1 user would then prefer to remain comfortably seated and just use some tool to look at (and if possible, also interact with) what is on seat0's screen.
The first thing that came to my mind was to use TeamViewer. It is free, it is multi-platform and it would also provide for remote support if one of the two is not in the same room but somewhere away. But I can't get TeamViewer to work on neither seat0 nor seat1. It always complains about not being able to connect to the Internet. I suppose that this is due to the machine also running two small KVM virtual machines and therefore doesn't have a regular "eth0" network card, but a bridge slave device instead.
I did then also have a look at various RDP and VNC servers, but those seem to be made to fulfill an entirely different requirement - they turn the computer into a terminal server where a remote user receives an independent session, like another virtual seat.
My need would instead be to grant remote access to an existing session on one of the seats.
Hopefully someone of you out there can point me in the right direction.
Thanks in advance, Patrick