Input Director is a free application which will help you to share your keyboard and mouse with multiple computers.
Earlier we wrote about Input Director here and we are using this for more than a year now. This application is improved a lot now. here are some cool new features (added after we wrote about it)
Can auto-switch between master and slave roles allowing you to use any mouse/keyboard to control any system
Can right-click on a network shared file in Windows Explorer and choose to open it on any computer running Input Director
Can bind a keyboard key (e.g. volume key) to a specific system regardless of which system is being directed
Shared Clipboard bug fixes
Fixed bug that blocked file copy/pastes from a Win7 master
I tried to copy a file from Windows 8 to Windows 7 and that worked fine. (if the folder is shared)
and many more read more here
So if you are using two or more computers connected in a network just like me, this tool will be very handy for you. I(f you are using an older version it is time to upgrade 
Here is my desktop
Two computers in which one is having two monitors.