I particularly like the "value" checklist point - this is really what differentiates a toy from a tool.
In 1999 Psion brought out the Psion7 / Netbook - if this device were given 3 or 4 things it would be my perfect portable device - a better screen, a better browser and wifi/bluetooth (and wifi calendar sync).
I have a Psion 7, battery life was 3-4 days of real usage, software sync was great, it had a proper keyboard, a 9 inch screen, protective (and very cool) builtin clamshell case, a touch screen etc ...
http://en.wikipedia.org/wiki/Psion_7
...in technology we never seem to learn much from great designs of the past ...