What all animation studios use for rendering such huge projects is clusters. They take hundereds of top of the line systems load them with whatever OS and clustering software they require and can use such techniques as parallel proccessing to get a job done in a 'reasonable' amount of time.

Buy clustering many computers lets say 100 1Ghz Machines with 1GB of RAM each, they end up with a supercomputer that runs at a realistic 100Ghz with 100GB of RAM(Logically of course)! Now imagine running all of this on a Gigabit Ethernet network and your talking about blazing speeds here. All under the power of a shell linux OS and clustering software (beouwolf perhapse?) makes this all possible.

This is a very cool suff, and sometimes very confusing when learning. I still am trying to work out the specifics of it myself.

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