#2 and #4 have actually already happened, they're just under the radar in the burgeoning (but admittedly still small) Hackintosh scene. Apple has tacitly abandoned the enthusiast market to home-made clones, and quite a few highly-savvy (and/or highly patient) Mac OS fans have taken advantage of that opening. Less technoid users are also getting into the act as very simple OS X installers for various netbooks are proliferating.
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