It isn't possible, The power of both the systems are almost equal making it impossible for one to emulate the other, on top of that the architecture and way the processors handle operations are completely different. I doubt we will even see one for the PC for years, they are just now starting to get a PS2 emu to work on a PC. Although a PS2 emu for the 360 is entirely possible. It is much stronger than the PC's out today so once they finalize the one for PC a one for 360 shouldn't be too hard, but it will still be a headache for whoever is creating it

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