yeah, but it would probably only be possible with a slim or later phat. older phats are limited since they don't use the vflash afaik. the NOR systems should be able to do it. it probably won't be done if older phats can't do it though. I remember Habib said that it's possible to use the same erk for all systems, in other words, you could replace the hdd in any system without format, but it would force a format the first time you changed it.