I thought there was a port of linux (or netbsd?) to sig3, although I can't remember whether it's fully featured or only command line?
Not that I've found - there's one for the Sig2 tho.
The sig3 only has 64MB of memory anyhow, and the ROM isn't flashable so it's a tad crippled for serious Linux work... What I think is almost unbeatable is the Sig3's form factor. There's room to shave a fair bit off the sig3 and still keep the screen and keyboard... Let me see if I can explain why it's near perfect.
But wouldn't that put it in the same size as the umpc? I'm sure some manufacturer is going to make a keyboard version or sony's next version will have a better keyboard.
The UMPC is a technical product looking for a marketplace. They don't know what people are going to do with it. What I wanted, and still want, is the Libretto u100 with a decent keyboard in that form factor.
Besides, the sig3 is nowhere near the size of a UMPC. When folded, it's depth (4" 5/8, or 117mm) is the same as the Z's width (4" 7/8, 122mm) IYSWIM. It's a few mm thinner, so fits better in a jacket pocket than the z. Widthwise, it's 188mm - about 7 1/2"... I find it easier to carry the Sig3 than the Z, but then again I use the Z in a Pdair case . It also looks a hell of a lot more serious than the Z. Dunno why.
I tend to take contemporaneous notes with the Sig3, and the keyboard and screen on the Z means that that is decidedly uncomfortable if i try the Z. If you've never tried a sig3 keyboard, see if you can - my bet is you'll be impressed bordering on amazed. It's better than any other small device I've found, from the Psion 5 to the Jornada 720 to the libretto 100ct or u100 to the g138 to the foldable USB offerings or Pocketop . It's travel is damn near perfect, it's responsive, and it's big enough whilst not being too big.
I also have a Smartbook G138 which is slightly bigger than the Libretto 100CT and runs WinCE .net 4.2. That is too big for the intended use.
Form factor and ergonomics are to me number one priority, with battery life second. The Z is a brilliant device but doesn't get as much use as it might because of the cramped keyboard and small screen. The sweet spot for me would probably be a width of 15cm (6"), depth of 8cm (under 3") and a height of 2cm (under 1").
That'd be big enough to fit a 5" 800x480 screen into, a good size 5 row keyboard with a travel that feels great, give enough space for ports (please can we have integrated video out - I can ditch my laptop then!) and still be small enough to take everywhere I want to take it.
I wonder if it's worth mentioning your plans to the good folk at hpcfactor.com (I moderate on their boards and write reviews for them)? It's a WinCE site dedicated to handheld pcs, but there's people on there who might have valuable experience or input when it comes to ergonomics?
The tech sounds great, and it sounds like having a slightly bigger form factor could give you some real advantages... 6x3x1... hmm...