It's been pretty much a flop so far, but there are signs that the Tablet PC could finally be ready for serious mainstream use.

Launched with a great fanfare in 2002, the Tablet version of Microsoft Windows was predicted to get 20 percent of the laptop market by the end of 2003. In 2005, its share is still languishing at a few percent.

As we said last year, the Tablet was too expensive, too different and too heavy.

Nevertheless, the idea is good, and anyone who has played with a Tablet responds positively to the concept of using a pen to write on the keyboard with digital ink.

Microsoft has plugged away at the details, and the Tablet operating system, and its related applications are now a lot more user friendly than they were. With a new generation of hardware emerging, it may be time to take a new look at Tablets.

Thinkpad endorsement
Perhaps the biggest sign that things have changed is the availability of a Tablet in the Thinkpad range, normally one of the most sensible and staid of laptops (butterfly keyboard notwithstanding).

The X41, launched this week, is the first Thinkpad Tablet, and the first Thinkpad from Lenovo, the new Chinese owners of the brand.

IBM has spotted the possibility of classing a Tablet PC as an "ultraportable", a class of machine that traditionally commands a premium. It's at the high end of the weight - and price - range for ultraportables, but at £1290, and 3.6lb, it's viable for a mobile professional.

The device looks well designed, from photos on the web, with a fingerprint reader for security, and all the USB slots and network ports you would expect on a laptop of its class.

Something has to go, of course, and it's the optical drive. For the same weight, you could have a laptop with a DVD in it, or a laptop with a twistable screen, that converts to a slate. That's the choice Lenovo is giving you.

You can have a DVD drive, of course, in the docking stations.

Motion Computing - the real innovator?
IBM isn't the first to get to this point or even - possibly - the best. Motion Computing has been the leading innovator in Tablet PCs, and it came out with its own lightweight Tablet earlier in the month.

We have yet to hold either machine in our hands, but Motion Computing's LE1600 has had plaudits from those who have used it. It includes features that are still not part of the basic Tablet edition of Windows XP, but are in Microsoft's plans and prototypes.

It has three microphones, so it can pick up good sound, no matter which way you are holding it (this is important, as the Tablet is intended to take notes and record, while being held in the crook of your arm or rested on a table).

It also includes a sensor that reacts to ambient light to keep the screen visible wherever you are, while still saving on battery power. It also has a security suite and - like the X41 - a fingerprint reader so you can use to stop other people using it.

The biggest difference is that the LE1600 is a pure slate. It is made of carbon fibre and magnesium, and the keyboard is an optional extra that clips on. Without the keyboard, it's a sleek, light beast weighing 3.13lb, with it, it's still portable.

Other contenders
These two are not the only devices in the new wave of Tablets. Fujitsu's LifeBook may be the one for people who really need to carry a DVD drive - it fits one in a £1275 device, that weighs an extra 1lb. This one also has Bluetooth, and a feature that is reminiscent of a PDA - one-touch buttons to launch applications.

There are other players with recent Tablets including HP, and the choice looks like getting broader, as the Tablet operating system becomes more sophisticated, and Intel's mobile chipsets are refined.

Make way for Apple
Indeed, one player that may arrive this year, is Apple. Reports surfaced recently on the Web, that Apple has been granted a patent (US patent No. D504,899) for a Tablet-style Macintosh. Other sites contain brief descriptions of a prototype.

It may come to nothing, as so many Apple prototypes do, but there would be a lot of sense in Apple - whose products are already less dependent on the keyboard - creating a computer without one.

We were reminded recently that Apple was around at the start of pocket-sized PDAs ten years ago, with the Newton (indeed, its investment in handwriting recognition for the Newton is what gave Palm its start).

This time round, Apple would have less chance to claim precendence, as Microsoft has done a lot of the groundwork. We hope that's not the only thing making it wait.