Maybe when you're in your home office you'll dock it with a keyboard, mouse, and two monitors, and use it as your workstation.
The point is, I look forward to the day when physical device size no longer really correlates to usable power or storage space, and THAT means that, barring supercomputers and servers, most people will have just their "phone". What that device acts like will be based on which I/O peripherals you plug it in to.
A guy can dream...