The OS isn't a problem. Consider Linux inhabiting spaces from embedded (32M ram and a little flash is comfortably doable with Debian, this is a small fraction o

The OS isn't a problem. Consider Linux inhabiting spaces from embedded (32M ram and a little flash is comfortably doable with Debian, this is a small fraction of an iPhone) to 87% of the top 500 supercomputers on the planet (top500.org). The user interface is a whole different question. Apple considered this question and decided that phones are too small to share a user interface with modern desktops. 9-10" displays are somewhere between. My personal observations on display size and desktop designed user interfaces: 24", 20", 15", and 13" are all nice and I don't feel cramped or diluted on any of them. On my 9" netbook I resent the area lost to non-core display tasks (menu bars, icons, all the spacing and stuff that makes it work well on larger devices). But after abonding the desktop metaphor, on my 4"(ish) iPhone with its size sensitive applications I don't feel cramped.