There is something about the idea of having a complete computer in your pocket that is very alluring. In a way it is what PDAs are all about, but even the best PDAs don't offer what a full PC or notebook computer can.

That's where the OQO model 01 comes into play. It packs a complete Windows XP Professional solution in a box measuring 125 x 88 x 22mm. That's bigger than your average PDA, but not by much. Does it work?

Well, there's no doubt that Windows XP runs, nor that the OQO model 01 has a great 'wow' factor. The Transmeta Crusoe 1GHz processor doesn't provide a great deal of oomph, though, and the 20GB hard drive is rather smaller than you'd expect to get in a notebook. The 256MB of RAM will struggle if you have lots of applications open too.

These points matter because the OQO model 01 is not just a pocket-sized computer designed to live alongside a main machine. If you can afford to add more cash to what you are paying for the OQO model 01 already, you can attach an external monitor and keyboard, effectively getting yourself a desktop computer. But it will be a low-powered one that is vastly over-priced and under-specified when compared to what else you can get for the same money.

The extra hardware is attached via a cable, but there are some connectors on the OQO model 01 itself too: for FireWire, USB (1.1), and headphones. And both Bluetooth and Wi-Fi are built-in.

Standing alone the OQO model 01 has a slide down keyboard with small but usable keys. Touch-typing is impossible but we managed to write this article on it, albeit rather slowly. There is a separate number pad and a nifty mouse substitute comprising a 'nipple' which sits between the QWERTY section and the numberpad, and two buttons located on the far left of the keyboard.

If you don't want to use the keyboard you can slide it away and pull out the digitizer stylus instead, as the OQO model 01 has a touch-sensitive screen like that found on Tablet PCs.

The battery delivered MP3 music for just about three and a half hours. We forced the screen to stay on throughout playback, so in the real world, if you let the screen go off, you might get more life than that. In this department, the OQO model 01 will put many notebooks to shame. However, we had to pump the sound through headphones as there's no speaker on board.

The OQO model 01 is a great little computer, and we'd have one tomorrow if we didn't have to pay for it. But it really can't function as a standard computer unless you fork out for the external monitor and keyboard, and have low level computing needs. In the end, then, this is nice kit, but probably not very practical outside of a few specialist areas.