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If anyone can make usable laptops impossibly small, it's Sony.
The TZ21WN is the latest in a long line of ultraportable machines that are tiny enough to carry around with you nearly everywhere you go, yet big enough to do some proper work on without squinting or wishing you didn't have sausages for fingers, although it will set you back around £1,600.
The TZ21WN may only be equipped with a 1.06GHz Intel Core 2 Duo U7500 processor, but it makes the most of what it's got. When combined with its 2GB of RAM, it turned in a PCMark05 performance score of 1,877 which is impressive for something this size and weight.
Where it really shines, however, is battery life -- this is a machine that just keeps going even when it's being pounded by Battery Eater's intensive test. It managed to last a whopping three hours 25 minutes before giving up. The less strenuous reader test proved hardly a match for it and it kept going for a staggering five hours 35 minutes.
The 11.1-inch screen features a carbon fibre lid to protect it from damage, which is just as well as it's impossibly slim at just 4mm. The glossy X-black LED screen is a joy to use, provided there aren't any bright lights behind you to reflect in the display.
The keyboard is great to type on, despite the fact it's been squeezed into such a small chassis. There's even a fairly large 3mm gap between keys, which cuts down on mistypes. The touchpad is a decent distance from the spacebar, so you're unlikely to accidentally activate it while typing.
As well as your usual Wi-Fi and Bluetooth wireless connections, Sony has also gone one extra and included an integrated 3G HSDPA adapter, so you'll be able to get fast Internet access wherever you go, provided your destination isn't a Faraday cage.
Sony has also managed to squeeze a DVD writer into the right hand side, leaving you slightly wondering how there is space left inside for the rest of the components.
The TZ21WN may be no slouch when it comes to application performance, but it's woefully under-equipped for 3D gaming. It only managed a pitiful result of 124 in 3DMark06, so you'll need to stick to Scrabble on Facebook rather than Halo or Half Life.
Its small footprint also means there's not that much space to cram in ports and connectors. You do get a new ExpressCard slot, rather than the outdated PC Card expansion, but there are only two USB ports and they're both on the same side, which doesn't offer much flexibility for positioning peripherals. You also get a 4-pin Firewire connection, modem, Ethernet, headphone, microphone and VGA.
With a tiny footprint, lightweight construction and 3G connectivity along with Wi-Fi, the TZ21WN is a traveller's dream machine. It's got enough power to do sensible things on and will last an incredibly long time while it's at it. Provided you can forgo gaming, it's an excellent little model, costing around £1,600.
Edited by Jason Jenkins
Additional editing by Jon Squire