MaxiVista is an application which allows you to control mutiple PC's with 1 keyboard and mouse utilizing TCP/IP (your network).

http://www.maxivista.com/



The added functionality it has compared to its counterpart Synergy is that you can pull applications from 1 PC to another seamlessly.

Although it is not open source they do have a free trial available.
As well you cannot broadcast keystrokes with this application.

Learning Curve - Medium

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