Sony's _<A HREF="https://wikipedia.org/wiki/Sony_Vaio_P_series">Vaio_&nbsp;P_</A>: 
an ultraportable Windows PC that was small enough to qualify as a handheld 
computer but too big to fit in a pocket.  I wrote most of 
the 1600-page _<I>Programming Python, 4th Edition_</I> on this 
(and boy are my fingers tired...).