That gives some interesting possibilities for computers in a few years -- one relatively expensive drive for code, another cheap drive for data, for example.<p>Probably 80% of your hard drive is stuff where the access speed is irrelevant -- movies, for example, since your capability to read from the disk far outstrips your eyes' capability to watch the movie. Photos, Office docs, email, ditto ditto ditto.<p>Then there are programs -- or even a subset of programs, really -- that actually have appreciable startup times. Office, Eclipse, etc, I'm looking at you.<p>You could put those programs on the "fast" disk (along with most of the OS, presumably) then make it as big as you pleased with cheap spinning platters. With a little bit of software trickery, you could present the two disks as one physical drive to the operating system (or to the end user) and shift data between them using some sort of caching policy (LRU, whatever).<p>It sounds like a sexy idea for servers too -- can't afford to keep the entire working set in RAM? No problem -- back up the RAM with solid state and only write to spinning magnetic media when you need long-term non-volatile storage.