This trend has been led by Hewlett-Packard with its OmniBook line, especially now that they have colour models of their light-weight wonders in the form of the new OmniBook 600C, which sports up to a 486-DX4 75MHz processor.

But now the OmniBook has a real competitor in the form of the new HiNote Ultra from an unlikely source - Digital.

The firm spent the last half of 1994 making waves with its head-first re-entry into the highly competitive PC market. For many observers, the high-point was the launch of the new HiNote and HiNote Ultra notebook lines in New York and San Francisco just before Comdex last November.

The HiNote Ultra is the jewel in the crown. While the HiNote is just another entry in the conventional notebook market, it has neither the sleekness nor finesse of the OmniBook or the HiNote Ultra, the latter aims to set new standards.

Combined, the HiNote Ultra and HiNote boast an impressive 13 patents either received or applied for, several of these linked to the Ultra's unique design which makes it the thinnest portable on the market. While it is not possible to say it is the smallest and lightest, a claim probably more suitable to its HP competitors, the Ultra is indeed the sleekest at a depth of just one inch.

More than this, though, Digital has tried to design-in features which help the new model live up to the 'technology touched by art' slogan which accompanied the notebook's launch.

The HiNote Ultra's Lithium-ion battery, for instance, doubles as the fold-down footrest. So rather than being in an awkward square-shaped cavity inside the machine, increasing the thickness of the notebook, the Ultra's battery attaches to the rear of the unit without increasing the thickness and then rotates down to help provide a more comfortable typing angle.

When folded-down, the battery produces a triangular-shaped wedge underneath the unit where a zero-footprint, cable-less floppy drive dock attaches to a single connection port on the base of the notebook. This allows the external floppy drive and the notebook to become a single unit which can easily be carried around without worrying about cables or a separate drive unit.

To help increase portability, the power-supply for connecting the unit to the power-mains is smaller than most other models as well as weighing no more than nine ounces, making it an easy addition to any notebook travel kit.

Other ergonomic features include a PowerBook-like palm rest with a centre-placed trackball, with a main button which wraps all the way around the bottom and both sides of the trackball, making it easy to use for both right-handed and left-handed users.

There is also an LCD status display which provides information about battery life, power source, drive access and other features including shift-lock and num-lock.

The keyboard sports full-size notebook keys, inverted-T cursor controls and reasonably well-sized function keys. While some may find the keys have a little less travel than they might like, it didn't take long to become accustomed to the keyboard and to type almost as quickly as with a desktop PC.

Making it easier to type at full-speed are the large left-shift key, control and alt keys on both sides of the space bar and the large enter key.

On the processor side, the HiNote Ultra sports a complete range of processors and screen combinations from a basic 486-SX 33 MHz unit with a monochrome display to 486-DX4 75MHZ combined with a TFT active matrix colour screen.

Disk drive size ranges from 170MB to 340MB on the high-end and the unit comes with two PCMCIA Type II slots (which can alternate as one TYPE III slot). What is especially attractive is the basic floppy dock can be switched with an optional dock that adds not just a floppy drive but two additional Type II PCMCIA slots. Digital hopes this will make the system a complete desktop replacement.

Indeed, one can clearly see that with the built-in external keyboard, video and serial and parallel ports, along with four Type II PCMCIA slots, it would be possible to add a network card, a fax/modem, a SCSI card and sound card to the HiNote Ultra without significantly increasing the size or weight of the unit, and yet still provide most of the features the average business user is likely to need.

Still, it would be wrong to say the HiNote Ultra is the perfect portable. While it does have some of the most innovative features making it an attractive option, there are some quirks to be aware of. None of them take the machine out of contention for the top ultra-portable spot, though.

These problems include the fact that the unit's front right corner can become particularly hot while charging and occasionally the floppy-drive indicator will come on and stay on even when the drive is clearly not being used.

Also, the way in which the case curves inwards at the front means the front corner of most PCMCIA cards protrude slightly, rather than being flush with the edge of the machine. Likewise, for someone with large, clumsy fingers, the PCMCIA release switches could be a little awkward, although workable.

The real test of any notebook, though, is in its use. What is it like to carry it on a trip and use it in common situations? The slimness of the machine makes it easy to carry with papers in most bags and briefcases and its lightness, even with the floppy drive attached, really wasn't an undue burden while walking long stretches in airports or on city streets.

Likewise, its compact size made it easy to use on most airline-tray tables and the display's lighting was sufficient in the dim conditions often found on aeroplanes. Particularly useful was the zero footprint of the floppy drive and the lack of cables which made it easy to attach and use while travelling.

The machine's claim of a four to six hour battery life seemed fairly accurate. By paying basic attention to the way one uses the drives and PCMCIA devices, it is definitely possible to get more than four hours of use out of a fully charged unit.

The real test of the unit is in terms of durability. The main unit seems quite resistant to scratches, although the small rubber pads at the bottom of the battery/foot rest seem prone to peeling off. Even so, they are not vital to the operation of the unit nor its stability for typing.

Another inconvenience is the fact that the port cover is not attached to the rear of the unit and only consists of a simple piece of flexible rubber. Indeed, it may be this prevents the cover from being broken, but it really seems an unnecessary addition. After all, the battery, when not in use as a footrest, covers the ports at the rear of the machine, making the difficult-to-attach rubber cover just a nuisance.

More serious, though, is the durability of the connection between the floppy drive and the main unit.

The dock attaches by two simple metal hooks at the rear and the plug nearer to the front of the unit. Next to the plug is a screw which further ensures the drive remains attached while in transit.

Unfortunately, there were times when the screw didn't seem to catch easily and one of the metal hooks simply broke off in normal transit.

With the screw and plug, one hook is enough, but it is easy to see that if both were to come off, users might have a less than secure connection.

Still, this may be a trade-off for convenience compared with the standard cable-attached approach adopted by most competitors and it isn't enough to warrant disregarding the machine as a serious option for an ultra-portable.

The degree of wear which the unit will be subject to should be considered, though.

The biggest drawback is the price. A high-end DX4 75MHz model with an active matrix screen costs $40,895. A competing OmniBook 600C tops out at around HK$28,000, although this is with a dual-scan display.

If prices were to come down just a bit, the Digital HiNote Ultra, with all of its design features, would likely be a top player in the ultra-portable market.