i remember a while back reading something about how it could be possible to hack a 360 through a system update. the only problem(well maybe not just one) would be that if you modified the update code at all it'd break the signature, making it useless.
well i thought perhaps if one could be able to extract an ms-signed signature from an update and then inject it to a modified update (much like the psp's custom firmware) it could be possible foll the 360 into thinking it of an actual update. thus allowing us to run unsigned code on most consoles. it would be much more efficient(and far less time consuming) than a jtag. please don't torch me if this has already been proven impossible.
btw, im pretty sure if we really did some research and experimenting this could very well be possible. post your thoughts, but like i said please don't torch me if its been disproven.