Sony has launched the first Vista-based ultra-mobile PC which it hopes will appeal to business users looking for mini laptops.

The bad news is that "less is still more". In this case in the form of the wallet-crunching £2,000 ($3,800) price tag that comes with all this miniaturisation. The company’s original take was launched with Windows XP last spring as the VGN-UX50.

The matt-black Vaio VGN-UX1XN, or VX1 for short, measures just 95x 50.2x32.2mm with a slide-screen over a full Qwerty keyboard. It weighs in at less than half a kilogram and is the smallest computer that can claim to do everything its A4 laptop rivals can, including running the business edition of Vista.

The specification is not that far removed from a basic Vista laptop either, packing in 1GB RAM, Intel’s 1.33GHz low-voltage U1500 Core Solo chip, onboard 802.11g Wi-Fi, an Intel-based graphics chip, a USB port, Bluetooth, a Memory Stick Duo port, and sockets for a microphone and headphone.

The main difference is the shrunken screen, a 4.5 inch, 1024x768 X-Black LCD, and the slimmed down keyboard, which has its own blue backlight to aid use in low light. There’s no hard disk however and users having to make do with the built in 32GB flash drive.

The clever bit is probably the way the screen folds over the keyboard when not in use, reducing the unit’s bulk. As with UMPC devices based on XP (formerly known as project Origami), the UX1 can be used in landscape or portrait mode, and combines the keyboard with a touch-screen and stylus.

Because this is a Vista-based machine, and customers are assumed to be businesses, the UX1 has integrated support for a Trusted Platform Module (TPM), and a fingerprint recognition system. There are two cameras, a 1.3 megapixel one on the machine’s rear for taking snaps, and a 0.3 megapixel one by the screen to help with video-conferencing.

If potential buyers are a bit leery of so much new technology in one pricey box - the Origami-derived XP platform has not been a big hit so far - Sony is keen to put them at ease, especially over the appearance of flash storage technology.

The company points out that flash drive operations are faster to load than a hard disk, are less prone to fail under shock and vibration, and use less power due to there being no moving parts. Equally, magnetic technology has a defined level of reliability businesses have become used to working with, unlike flash. As anyone who has had problems with flash memory in digital cameras will tell you, the technology is far from being a storage panacea.

The official press release made no mention of any 3G capabilities beyond Wi-Fi, nor the price for the UX1. The £2,000 tag is believed to be correct, however, having been mentioned to third-party sources by Sony officials.