OT: introduction to computing clusters?

[skip at pobox.com]

Sorry for the off-topic post, but I know of no better collection of brains
than this one.  I'm starting to investigate clustering as a means to address
some growing computing needs at work, but know essentially zip about the
concept.  If you know of a good introduction to computing clusters (Linux or
Solaris would be the software environment), I'd appreciate a reference.

Thanks,

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