Ge64, this is one of the best ideas I have heard in a long time.  I can't beleave that nobody has thought of this before.  Its would be like the super console of all time!!  I have 3 PS2's, 2 gamecubes (I have access to more very cheap), and no xbox (though I could get one cheap). I am very good at fixing/taking apart the PS2 because I have fixed so many.  So i have some PS2 hardware skills. I have a few hard drives laying around (2 of them in Ps2's and one external 500gb).
I would love to somehow help but in a way this project sounds a bit out of my skill level, it would be very hard and cost ALOT of money, and take alot of time.