QUOTE(wr_uk @ 01/06/07, 03:40 PM) [snapback]256520[/snapback]
I'm thinking about buying Shake for PC but I have a feeling it will only run on Linux and Mac.
correct
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Is it possible to run Shake on XP or do I need to install Linux?
you can only run shake 2.5 on windows which is not supported and sold anymore (see above)
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If I do need to install Linux is it easy to install.
depends on your machine and your skill and luck 
why dont you just try on a seperate partition and see if it works on your hardware?
i'm not sure if apple has dropped the linux version in price as well, if not getting a spiced up mac pro (3000) with an osx shake licence (500) will cost you less than a linux licence alone (5000) with much less headache and probably the fastest hardware available.
i suggest talking to an apple reseller
++ chris