Server OS spanning mult. computers

Good day, fellow followers of /comp/.

I have a question for those 'more experienced' folk in the community.

Does anyone know of a server Operating System that will span multiple computers, a.k.a. use each ones processors, hard drives, etc.? I'm aware of Cluster Knoppix, but no work has been done on that in years, and it's not really server oriented.

Any suggestions/ideas?

Nothing...?

Well, that's disappointing...