Looking for a virtual desktop solution

I have 3 computers on my desk, a linux box, a windows laptop and a windows box. The linux box and the windows box are plugged into the same monitor, I switch sources on the monitor to change over, and use Synergy to share my mouse and keyboard over the 3. Essentially I'm looking for a software solution that removes the manual switching of the monitor and allows me to virtualise a desktop environment which duplicates exactly the desktop of the linux box. I want a simple TRANSPARENT solution that lets me just run my mouse off of the right of my desktop onto the left of the same screen but another remote desktop. Anybody got any ideas?

Regards, Kye

 

If you wanted to use several monitors http://www.blackbox.com/Store/Detail.aspx/ServSwitch-Freedom/KV0004A Video demo:http://www.blackbox.com/Resources/Library/Video/video.aspx?vid=84

It might be cheaper to open a few VNC windows to switch between machines via ALT-TAB. But I have yet to see a program that would swap 3 screens on one monitor becasue you move the mouse to the edge, sounds interesting though.