VLC can do this if you cleverly setup broadcasting and define rendering areas. Might also need to set sync or delays. There is also a videowall feature. Oh, and VLC is free and multiplatform.

Or you could do it on 1 machine.

What uhhh resolutions are you running there? Even full HD is only 2 megapixels or so. (720p is only 1 MP).

A 17" monitor at 1280 x 1024 is 1.3 MP or so. It would be watchable but why? Bezels alone would be a huge distraction.