I'd like to see basically the N800 with the following modifications, all intended to make a pocketable, stylus-oriented, mobile computer/media player:

Change to microSD (2 of them)
Slightly larger screen, still 800 x 480, but smaller form factor
USB OTG without special connectors
Get rid of the camera
No keyboard, no cell connectivity, no phone
Lower price, lighter weight, more power, better throughput to the screen