I've always been in favour of interconnective devices that serve each a single use, for example you would have a touch screen without a heavy cpu with just a bluetooth adapter which would be use to send and recieve the visual and input signals to a cental processor box, then you would have devices like and audio device you would have round your neck, and also a drive unit to insert games and data. And the whole system could be linked to a mobile phone (with or without screen as the whole setup already has a screen).
What all that would do is give you a minimal ovelap of devices, cos atm is i have a palmtop and mobile phone and an mp3player, i have 3 Screens, 3 Speakers, 3 Processors.
So decentralizing all your gadgets and giving them a single use for which they were bought would save space and make it cheaper.