You may recognise the Libretto name from the distant past, when handheld PCs were all the rage, but while this Libretto U100 may look and feel like the 90s original (a laptop PC about the size of a VHS cassette, to use the marketing vernacular of the time), under the skin it's a completely different animal.

This ultra-portable sub-notebook has bang up-to-date technology incorporating a fast CPU, a serious amount of storage space, more than enough methods of communicating with the outside world and Windows XP as the Operating System.

While the original was powered by a 266MHz Pentium MMX and 64MB RAM, the new U100 comes with an Ultra Low Voltage Pentium M 753 (1.2GHz with a 400MHz FSB speed and 2MB of L2 cache), i855GME chipset and 512MB of DDR400 memory, all of which means plenty of power for your applications while at the same time getting the most out of the 3,400mAh Li-Ion battery.

While the Libretto itself measures 21 x 16.5 x 3cm (W x D x H) and weighs a mere 0.98kg, adding the bundled SuperMulti Dock raises the weight to 1.43kg. The docking unit houses a DVD+/-RW drive complete with player controls which turn the Libretto into a perfect mobile DVD player; you don't even have to boot into Windows to use it.

The Libretto sports a 7.2-inch Widescreen (WXGA) display with Toshiba's TruBrite technology, and its high 1,280 pixel by 768 pixel resolution is ideal for watching DVD movies on, but not so good for reading text at any reasonable distance from the screen.

With a notebook this small there has to be some compromise (aside from the screen), and with the Libretto it's mainly the keyboard. At 75 percent as big as a full-size keyboard and with 12mm spacing, it's not the easiest thing to type on, but having said that none of the other ultra-small notebooks available offer much better typing experiences. The Libretto's pointing stick is positioned not in the middle of the keyboard as you might expect but in amongst the mouse buttons, which takes a bit of getting used to but is probably sensible.

For storage the Libretto U100 uses a 4,200rpm 60GB hard drive which comes with a crash prevention module; when it detects any sudden movement or vibration, it automatically parks the drive's heads in a safe position to prevent data loss. There are also PC card and SD card slots for additional storage, plus you get two USB 2.0 ports.

To connect to the outside world the Libretto is blessed with a number of options; 802.11b/g Wireless LAN, Bluetooth with EDR (Enhanced Data Rate), 10/100Mbps Ethernet and a V.90 modem. What comes as a complete surprise is the Fingerprint reader for added security, and this is easy to set up and use too.

By virtue of its Ultra Low Voltage CPU, the Libretto has a very useful battery life of just over 4 hours, but you could probably get even more out of it by carefully fine-tuning the power save options. Toshiba supplies a 3 year warranty with the unit.

As with the original, the latest Libretto will make you think about the uses you could put it to, but perhaps the most limiting factor is the price.