This is a really useful program if you ever use two computers in the same room such as a laptop and desktop. It basically allows you to use one keyboard and mouse on both computers with options to allow the mouse cursor to go off the side of one screen and appear on the other. I’ve used it on both my laptop and desktop where it allowed me to use the laptop keyboard and trackpad to control the desktop.

In addition to this it also allows you to copy and paste between the computers. You can use it with up to four computers as far as I know but that seems a bit like overkill to me. Link to the article and download below.
Microsoft download from The Garage: Mouse without Borders – Next at Microsoft – Site Home – TechNet Blogs.