You can get linux for free if you get hooked up with a user group. almost all major cities have them and they are a great resource. where im from they have install fests where you can take your computer and talk with gurus and have them help you install linux. im not sure but im pretty sure red hat doesnt run on mac. i think the best one for the powerpc is yellow dog. personally i would just install osx cause you have to mess witha lot of crap to install linux on a mac. its not as easy as people will tell you.
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