Cluster computing for dedicated game server?

Title says most of it, would that work? I have a few computers sitting around doing nothing and an in-house server would be very nice. I have done a bit of research on how to set this up, but most of it centers on how to set up more academically based clusters. I have not as yet been able to locate something that describes setting up a cluster for the express purpose of running a dedicated gaming server. Does anybody know more about this?