ParallelKnoppix
ParallelKnoppix is a remaster of Knoppix that allows a cluster of machines for parallel processing using the LAM-MPI and/or MPICH implementations of MPI, as well as PVM. You can convert a room full of machines running Windows into a Linux cluster, and when you shut down, your Windows machines are in their original state. The computers in the cluster can be homogeneous or heterogeneous. Getting the cluster up and running takes about 5 minutes, if the machines have PXE network cards. Clusters from 2 to 200 machines are supported. The tutorial explains in detail how to set it up. A security enhanced version was released December 2, 2005. ParallelKnoppix 2.6 was released May 4, 2007. PK 2.8 for 64 bit systems was released November 21, 2007. This was the final release for ParallelKnoppix. See PelicanHPC for the continuation of this work.
ParallelKnoppix Official website
Download link to the distribution ISO