I guess this is redundant for ppl who have a VNC server installed on their computers and a VNC viewer on the iPhone.
I've been using it for a few months now - to access my computer through the iPhone remotely.
Check out Mocha VNC or Real VNC if you're interested.
Conversely, I also have a VNC server component installed on the iPhone to allow me to control / view my iPhone through my computer... this comes in handy if I need to put my iPhone screen on projector during a presentation, or take screenshots of my iPhone apps for a video or document.
Check out Veency on Cydia if interested.
This is not controlling the monitor, its just the touch-pad application, like the track-pad on laptops. Hence it sorta acts like a KVM switch.
For taking screenshots of iPhone all you need to do is press and hold the Home button and then press the Power button. And that's your sceenshot.
PS: Esix, yaar, when you come across cool stuff like that you're supposed to tell us na.