If you’ve got multiple computers at the same desk, make sure you check out Win2VNC, a great program. It allows you to use the same keyboard and mouse to control both machines.
It works in an interesting way… you set up VNC (a remote desktop server) on your secondary computers. Run win2vnc on the primary computer where the keyboard and mouse are attached. When you launch win2vnc, it creates a remote desktop session along one side of the screen, so as you mouse over to that area, your mouse and keyboard switch focus to the secondary computer.
Note that the version here is older and does not have as much functionality as the project hosted at sourceforge (via the link above).