I'm using Win2VNC for a pretty long time and I've always liked it, especially since it got scroll wheel support. But I never thought it to be so very special, until someone told me "Wow, you can do that?!". Which got me thinking.. hmm wait, it is cool!
As the application name somewhat indicates, Win2VNC (based on the Linux variant x2x) is a windows to VNC connection. All in all not too special, other then that instead of replacing your screen with that of the new host computer, it expands it.
Effectively giving you a dual head system. Of course this is not entirely true, since applications are bound to the computer where they are launched. But your mouse, keyboard and (last but not least) clipboard are transfered very naturally over to the host computer.
So you have your work station, and your laptop, working with one keyboard and mouse. This works ideally with e.g. testing different browsers (ie7 and Firefox on one, and ie6 + Opera on the other)
It works by making a transparent, one pixel wide line across one side of your screen. Once your mouse is placed upon it, your mouse and keyboard are switched to the host computer. And the same way in reverse. If you run it on a local network (which does makes the most sense, obviously) the switch is hardly noticeable.
And another cool feature is that your host or client computer can run a different operating system, so you can have a windows client connecting to a Linux host with hardly any pain.
I use it with a lot of fun and it can be very nice for testing and certainly boosts my productivity. I mean come on.. who doesn't like a work area of 5040x1050 pixels (-:
Want to know more about Win2VNC? Visit: http://fredrik.hubbe.net/win2vnc.html Download a free* VNC server from: http://www.realvnc.com (The free version doesn't run on Vista)