Cluster Computer, how does it work/how to build one?

I don't know which Forum this would belong under; so sorry if this is the wrong place to post this. I stumbled upon a video on youtube which explains how to create a cluster computer using raspberry pis. This got me intrigued and I would love to build one for myself; except I want to use two full sized mother boards and multiple GPUs. The idea being creating a powerful gaming rig. The most important question being, is this even possible? (I know cluster computers work but do they work for gaming?) If it does, What kind of hardware and software would I need to get started? P.S - Sorry if this question as already been asked; if so, just link me the page.

I doubt it.

It is possible... but not ideal. It actually has a negative impact on gaming performance (from what iv read)

http://www.tomshardware.com/forum/296979-31-gaming-cluster

http://ubuntuforums.org/showthread.php?t=901805

https://en.wikipedia.org/wiki/Computer_cluster

 

Just saw this video on cluster computer (super computer) - 

https://www.youtube.com/watch?v=hSVo4ejZ7rc

 

There is absolutely no reason to do this... A single motherboard and the components that can be installed to it are in no way limiting in regards to gaming. I think you are creating a problem where none exists.

Not creating a problem, just out of curiosity. If it is possible I would like to build one for the heck of it. I don't plan on making one like in the video. Just two computers.