OK, I guess I've been out of the loop, because this is the first I've heard of PCM. Sounds like pretty crazy stuff, but I doubt it'll be the next memory technology to hit your desktop.

"PCM is long-researched form of memory stores data by reversibly changing the state of a material from an amorphous to a crystalline structure. With the potential to story data when power is removed the technology could be a long-term rival to flash memory, although lengthy research at numerous sites over several decades has yet to produce a commercial phase-change memory."