Richard Lewis writes:
The Sharp Zaurus SL-C3000 is quite desirable in this area. It has there own Linux brand on it with Qtopia as well as being the first PDA with an internal hard rive! It has a whopping 4GB. Its small and clamshell-like (reverseable as well) with a keyboard suitable for thumb typing (and maybe normal as well, I've never tried).
I have a Z (the C760) and a colleague has the C3000. (Mine's a Japanese import, my colleague's via a German importer.) The underlying Linux is fine but, unless you subvert the machine with the Debian ARM distro, there's a dearth of application software. And it doesn't run X. For entering data, if you're willing to use <shudder> vi, it'll work off the shelf. The keyboard takes a little getting used: just don't expect to type a book on it!
I *wish* Psion had made it possible to put Linux on their 7 Pro. That's be a lovely machine.
For mainstream mini-laptops, the main choice is the dinky JVC machine (even seen one in PC World), though Toshiba is selling a new Libretto (the 1000, I think) in the States.
Mini ITX? http://www.uklinux.net/linuxpcs/. Or maybe even the Mac Mini?
Both these would be fine. We use mini-ITX boards in our wearables and they're robust, though you have to box them yourself. (There are some imaginative boxes around the 'net. :-) And I like Macs: OSX is a good Unix, though there are issues with X on Tiger that haven't yet been sorted out.
HTH.
..Adrian