It would be one of the lesser-sucky keyboard addon ideas. Still, allthough I liked my 5mx almost as much as my Newton (and in some aspects, such as the very clever screen zoom implementation[*] and the printer drivers, even more), I'm adamant in that Newton-like HWR for the N-IT would be much more useful and productive.

You see, if I have to lug around an extra piece of kit anyway, I'd prefer it to be a keyboard as near to fullsize as possible, and even the 5mx's keyboard was just that little tad too small to be completely comfortable.
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[*] For those who never experienced Psion, all Psion clamshell handhelds had a zoom function. "Yes, oh Stupid One," I can hear you mock, "So do the Nokia Internet Tablets. Duh!"

Ah, but you see, Psion's zoom had a fit-to-screen option that was implemented in every application on the handheld. Also, the Psions would use different fonts for different zoomlevels, not "Times" and "Helvetica", but fonts with slightly different metrics, adapted to the bigger size, for your viewing pleasure. It made a difference, trust me.

No? Well, I guess you had to be there...