Computer clusters can be expensive to buy and expensive to maintain. My current linux cluster has 18 CPUs, and takes up about 13U of rack space in a colocation facility, and uses 17-18 amps of power.
The current line of Apple Macintosh computers, on the other hand, have up to 8 cores at 3.2 ghz per machine. While even at this configuration, it technically is not as powerful as my large cluster, it is far cheaper to buy, costs much less to run, and can double as a powerful desktop. It also would have the added benefit that it would not have to use ethernet to communicate between processors (a major bottleneck).
My back of the envelope calculations on performance is impressing. For the model I'm using, my cluster yields just under 10 model years per day of running. For this machine, based on CPU speed alone, it should produce 6-7 model years per day. This calculation could over/under estimate the performance in key respects. First, the cluster uses opteron processors, and the mac is Xeon processors. In theory, the Xeons should be a little slower at the same clock speed. Second, since the mac does not have to use the ethernet to communicate, the system could be much faster since ethernet tends to be a bottleneck on performance. Time will tell, assuming the model runs on this platform.
I'll be using this blog to document the setup and performance of this machine as the system is put together.