best way to run graphical BT4 from a server

[dninja at gmail.com (Robin Wood)]

Hi
I'm building a server that is going to go into a data centre and I
want to some kind of virtual machine software, probably either
VirtualBox or Xen, and in that I'd like to run BT4. What is my best
option to get a full BT4 X session back to my linux desktop?

To try to explain it another way, if I start VirtualBox on my local PC
I get a full screen window with KDE in it, I want that but with
VirtualBox running on the server.

I know that I can do X forwarding through ssh but is there a better
way? A friend suggested Xnest http://en.wikipedia.org/wiki/Xnest or
something that he thought was called xbsetg (can't find google
reference) that would let my start my main X session on virtual
terminal 7 then have 8 start a gdm session to the remote machine.

Last resort is something like VNC but I don't know how I would start
the remote graphical X session without a monitor

I think Xnest seems like the best option but wondered if anyone else
did this and what they used.

Robin