COCOA stands for COst effective COmputing Array. It is a Beowulf class supercomputer. Beowulf is a multi computer architecture which can be used for parallel computations. It is a system which usually consists of one server node, and one or more client nodes connected together via Ethernet or some other fast network. It is a system built using commodity hardware components, like any office desktop PC with standard Ethernet adapters, and switches. It does not contain any custom hardware components and is trivially reproducible. http://cocoa.ihpca.psu.edu/.
26 WS-410 workstations from Dell http://www.dell.com, each consisting of:
Linux! In specific, RedHat Linux 5.1 distribution http://www.redhat.com.
Linux is a free version of the Unix operating system, and it runs on all PC/i386 compatible computers (and now also on PowerPCs, Alphas, Sparcs, Mips, Ataris, and Amigas). The Linux kernel is written by Linus Torvalds <torvalds@transmeta.com> and other volunteers. Most of the programs running under Linux are generic Unix freeware, many of them from the GNU project.
On the server, the following software is installed:
Approximately $100,000!