A little know feature of most operating systems is remote access. This is where your computer can see the screen of another computer, move the cursor, run programs, and so on.
These programs are also available for the iPhone, which means you can remotely access other computers when you are away from home. SolidSmack today talks about Jumi from Jumitech, and speculates on using it to design with SolidWorks on his iPhone, remotely. Um, no, the performance is too low.
I had installed NTCconnect software on my iTouch, as well as on my wife's single-screen computer. It works, though laggardly.
I wondered how it would operate on a three-screen system, like mine. At first, I was disappointed, because my iTouch showed a black screen. I clicked the 1:1 button to see the entire screen; still back. Then I realized NTCconnect was displaying the leftmost screen (screen #3), which I suppose it thought was the first screen (reading left to right). As I moved the cursor I came across screen #1 (middle, my main screen) and screen #2 (at the right.)
To NTCconnect, the three screens were one long, continuous screen. And it worked!
When I visit my in-laws this summer, I am installed NTRconnect on their computer. When I next see my dad, I'm installing it on his notebook computer.