x2vnc - 1.7.2-6+b2 main

This program merges the capabilities of x2x and vncviewer. It will allow a
machine with an X display and a machine with a VNC server running on its main
screen to act as if they were two displays connected to one machine. When you
move your mouse pointer off the screen in a direction of your choosing, the
pointer will appear on the other screen instead.