The Raspberry Pi is the equivalent of a hot glue gun (or duct tape) for the DIY/Makers. It's cheap, reliable and easy to use on any project. Even more so than Arduino (subjectively though)
My first computer was a Sol-20 (My dad still has this machine) and than I became a Commodore guy so I miss the days of talking Trash ;) between Pet-20 vs the TRS-80 days.
I ran into a journalist in the middle east a couple of years ago in a hotel bar typing away on an M100. He said that he still used it because it was the only "laptop" he couldn't break, the battery life was better than most anything else and his local bureau still had an analog modem and he could upload his story as long as he could find a phone line (internet not required). Apparently he's not the only journo working this way.
I've somewhat-considered doing a "clone" with essentially the same functionality, but with modern components, and a real battery. I'd guess you could get 2-3 days out of it.
By "real battery", I assume you mean a li-ion or some such. The fact that it doesn't use an exotic battery and needs only 4 x AA batteries that can be found just about anywhere was another bonus he touted. No charger to be lost. No strange power plug to be adapted to. No power source needed.
Other than that, I'm with you. Something just as rugged, with a somewhat denser display (80x24), very low power (msp430 comes in a couple of crazy low power variants and has plenty of oomf), bit more storage. Add maybe a PDF->text converter to the built in software and you're good to go.
That's true about the batteries. Maybe a pluggable battery case that could handle either. +1 for a denser display (and I might even argue for an OLED, but creeping featurisms also mean poorer battery life).
Hrm, might have to start working on something. There are some crazy low-power ARMs around too, I'd have to do a bit of research.
