Among the eight zillion products here at the Consumer Electronics Show (CES) in Las Vegas are some new iterations of the ultramobile PC (UMPC), devices the size of a paperback book that have touchscreens and run Windows Vista.

I didn't see 'em all, but I did check out Toshiba's technology preview of a UMPC it's working on. What Toshiba is showing is an early rough draft; the company won't say when the device might go on sale, and the demo shows one being powered by a fuel cell, something that's not going to happen any time in the short-term future.

The Toshiba UMPC packs a number of advanced input technologies, including motion sensors that let you scroll around by tilting the entire device around. The company is working on unique finishes that could make it better-looking than any UMPC before it. All in all, it's an impressive piece of next-generation technology.

And yet it looks like it'll be just as crippled as all its predecessors, because the whole UMPC concept is based on a fundamentally bad idea: putting a full-blown copy of Windows on a device with an undersized screen and no keyboard.

The Windows Vista user interface was designed to make sense on PCs with large displays and lots of pixels. On the Toshiba, text is barely legible, and the icons in the System Tray were so small I couldn't figure out what they were, period.

Like other UMPC companies, Toshiba has incorporated workarounds to deal with this, like a mode that magnifies part of the screen so you can actually read URLs as you input them into Internet Explorer. But that's inherently kludgy - shouldn't the default type size on a portable computing device be large enough to read?

The situation is similar with input. The Toshiba has the aforementioned motion sensors, several buttons for performing mouse-like manoeuvres, a mode that puts a virtual touchpad on the screen, and an onscreen keyboard that's broken into sections on each side of the screen.

Most of which merely compensate for the fact that Windows Vista is designed to use a mouse and full qwerty keyboard - items which UMPCs don't have room for. I've never seen a UMPC which rethought how you interact with a small computer from the ground up, rather than trying to work around Windows' deskbound origins.

As I got a demo of Toshiba's prototype, it dawned on me that one company has managed to make an UMPC that leapfrogs past all the ungainliness of all the other ones on that market.

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