If you do have more than one windows PC on your desk, you might find “Mouse Without Borders” helpful. It does allow you to share one keyboard and one mouse with up to 4 PCs and also share clipboard content between these PCs.
You need to install the app on all PCs and then connect them together. After that you can use mouse and keyboard from one PC on the other PCs just by moving your mouse pointer over the edge of your screen.
Main features:
- Control multiple computers seamlessly using a single mouse and keyboard
- Peer-to-peer system: Any machine can be a master machine
- Multiple mode: Keyboard/mouse repeat in all machines
- Shared clipboard: copy text/image/screenshot from one machine and paste to other machines
- Drag/drop file across machines
- Selective screen capture
- Support on logon/UAC desktop
You can find more information about that tool on this site. The download can be found here.
Mouse Without Borders