If you are interested in running unix tools on the HFS file systems, you should look into Darwin, and the now defunct OpenDarwin, but you will not be able to run the normal Mac GUI and most all of the commercial Macintosh applications. You could also look at sites about putting full OSX on the AppleTV, which would be applicable (and a preferable solution.) There are sites on the net which have instructions on how to do this for x86 OS X, which unfortunately has complicated hardware issues as well as questionable legal status. Theoretically, you would want to install X86 OSX as a native OS on your machine, preferably on its own partition, but I believe this might be against the latest Apple license agreement, which I think requires OSX to be installed only on Apple hardware.
