ThinkPad Dual Screen

I needed to use the VGA output on my Thinkpad to give a demonstration on Java Connector Architecture. A very short search later led me to this forum posting http://ubuntuforums.org/showthread.php?t=346555 that has a link to this http://ozlabs.org/~jk/docs/mergefb/.

Now I can use xrandr to turn on and off rudimentary screen mirror.

xrandr --output VGA --auto
xrandr --output VGA --off

I'll update here when I successfully get the desktop spread across both screens. As a word of warning, I just turned of xrandr VGA output (--off) and all running applications were locked. I could swap focus between them but the applications themselves did not respond. Beware.