Thank you Simon.
Well that's the desktop. Needs three A4 screens really to give an in-box/read-screen, an out-box/write screen, and an applications/help screen.
I just need someone to make me a 'Briefcase' computer with carrying handle, where the lid opens along its short side to that I can have the identical size A4 screen and a bay into which the same 'external' hard drive fits instead of having a drive of its own.
Or it could form the main computer with two additional screens when used in a Study at home or at the office.
It would need to have a decent (non-laptop) keyboard with a NUM pad and, possibly, a built in modular printer to give full capability on the move.