Input Director is described as 'Windows application that lets you control multiple Windows systems using the keyboard/mouse attached to one computer. It is designed for folks who have two (or more) computers set up at home and find themselves regularly sliding from one system to the other' and is a popular Mouse Sharing utility in the office & productivity category. There are more than 10 alternatives to Input Director for a variety of platforms, including Windows, Mac, Linux, Android and BSD apps. The best Input Director alternative is Barrier, which is both free and Open Source. Other great apps like Input Director are Synergy, Input Leap, Mouse without Borders and ShareMouse.
This program will let you use two screens on two different computers as if they were connected to the same computer. It even works between different operating systems.
