I set this up for a customer long, long time ago for 2D and 3D rendering for movie animation. I used clustered linux servers. Google is your freind
PS3 supercomputer clusters are actually the best out there but here's a wonderful build I use in scientific computing and I also rent out space on 3d rendering -- http://helmer.sfe.se/. Let me know if that helps you -- there's also the option of turning it into a research project and using the BOINC software to have people use their idle machine time on your project
Can your cluster be configured to resolve cryptpographic hashes, i.e., cryptocurrency protocols? Obviously, I'm not referring to SHA-256 or scrypt since there are far superior ASIC devices out there. I am referring to the lesser known hashes like Keccak, Grostl or CubeHash (or multiple combinations). How cost-efficient would it be? Or is it even realistic? OP, apologies for hijacking this thread.