It seems that more and more people are going for building huge clusters of machines out of commodity parts, and the interconnects between them and the software and configuration is what carries the real cost. Some pretty big clusters do run commodity OSes too - see Google, who run (probably heavily customized) Linux. Others run other things - for example, the world's top super-computer (maybe a tad over budget though

) runs CNK/SLES 9, which I know nothing about.
There are of course mainframes still around, but my understanding is that they are best suited to batch processing style tasks.
I guess the thing I'm really curious about, is what you'd find to do the power even if you did have it?
Jonathan
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