The Itronix GoBook (£2993 inc. VAT) is a fully ruggedised laptop, which means it's far tougher than the average machine, and built to meet various rigorous standards - including MIL-STD 810F.

This is a military standard that sees the laptop face extreme temperature, vibration, pressure and humidity testing, and it must survive being repeatedly dropped from a height of three feet. As with other fully ruggedised laptops, the GoBook also meets IP54 standards, which dictate that it must be a fully sealed unit - preventing rain, dust or other elements from causing damage.

The case, including the screen surround, is made from magnesium-alloy, protected by rubber inserts around the edges. The result is incredibly sturdy. You can even hose it down. A heated spindle warms the hard drive before booting up, so you can use the GoBook in temperatures as low as -23 degrees.

To make entering data easier, the XR-1 comes with a 12.1-inch digitised screen. Two styluses are provided, and clip neatly to the side of the screen panel.

With a resolution of 1024 x 768 pixels (XGA), the screen is a little cramped, but allows the GoBook to remain portable. The screen appeared bright in all conditions, including direct sunlight.

The keyboard is of a good size and is comfortable to use. The keys are constructed from luminous plastic, allowing them to remain visible in the dark.

Comfort factor

Thanks to the use of a dual-core processor - Intel's Core Duo T2400 chip - the GoBook copes fine when running multiple applications. Rivals use ULV (Ultra Low Voltage) processors, as being weatherproof makes it difficult to cool components.

Heat isn't an issue on the GoBook, however, because of a sealed thermal enclosure. This allows major components to be cooled by a fan, with separate air vents on the back and sides.

Unless you splash out on the options list, backing up your files will be a problem. An optical drive is not included as standard, costing an extra £225 (inc. VAT) for a DVD-RW. A card reader is also omitted, so copying files will have to be done by an external medium. You'll find three USB 2.0 ports for adding peripherals. These are also protected from the elements behind closable flaps.

Although it's an expensive option, the GoBook XR-1 is a natural choice for those working out in the open. Performance and usability are impressive, and the incredibly tough construction helps you get on with your job without worrying about the condition of your laptop.