The memory architecture is a very good point. It's fundamentally different from the x86-derived systems we all use today. Besides, if you really want to emulat

The memory architecture is a very good point. It's fundamentally different from the x86-derived systems we all use today. Besides, if you really want to emulate a Cray, it's not the OS that's important so much as that almighty FORTRAN compiler! Part of the fun of working with old Cray guys was listening to the ranting about how FORTRAN is the Best Language Ever and that by removing a layer of memory indirection, it's faster than even C. Of course, you're then hardcoding the living crap out of everything, but that was handwaved away as a minor price to be paid for real performance....