About as Small as You Can Get
Meet Sony’s ultra portable micro PC. It comes with a 4.5″ widescreen SVGA display and is powered by an Intel Core Solo Ultra Low Voltage processor.
The Sony UX180P also comes equipped with Microsoft XP Professional.
Just in case the image gives you the impression that the Sony UX180P is the size of your average laptop let me tell you that it basically fits in the palm of your hand.
The Sony UX180P may not be for everyone - I’m not sure my big fingers would be able to cope with that keyboard - the price is definitely not going to suit the size of my wallet 
You can read more about the Sony UX180P here.