Sony took the wraps off its Vaio UX50 ultracompact PC at a news conference in Tokyo on Tuesday, and I got five minutes to play with the ever-so-cool-looking device.It\u2019s about the size of a paperback book, so it fits in a jacket pocket, but it runs the full Windows XP OS and is based on an Intel Centrino processor.Dominating the front of the PC is the 4.5-inch liquid crystal display. This has a touch-screen so you can operate it like the previous Vaio U model as a tablet PC, but you can also slide up the display to reveal a full QWERTY keyboard underneath. The keyboard is backlit, which will be handy if you\u2019re using the machine in low light, but I found it a little difficult to use.The keys are almost flush with the case and don\u2019t move much when pushed, so I never really got a good feel for them. They\u2019re also small\u2014the entire keyboard is only about 12 centimeters wide\u2014so I constantly worried that my fingers were hitting neighboring keys, although in the brief time I used the computer I didn\u2019t get any misspellings.The position of the "enter" key at the far right of the keyboard made it difficult to press. This was compounded by its slightly curved shape to match the case.The screen is sharp and bright. It has 1,024-by-600-pixels resolution so full-screen Web browsing is possible, but would be difficult for the poor of sight. Everything in the Windows menus and input boxes was readable\u2014nothing was so small that it became a mush\u2014but I did find myself squinting at some things.There are a couple of handily located zoom buttons on the right-hand side of the case. These helped, although the need to include zoom buttons shows how small everything on the screen is.That may not be a huge problem because the UX50 seems to be more about fun, on-the-go computing than manipulating Excel files or writing novels. For many users, the portability of the device will more than compensate for the small keys and small letters.Because I had only a few minutes with the UX50, I wasn\u2019t able to test other features, although some of the more notable ones include a fingerprint sensor, built-in camera (just above the main display so you can video conference) and Bluetooth wireless. Sony is selling a companion Bluetooth GPS receiver that feeds global positioning data to the PC.It\u2019s difficult to hold the UX50 in your hands and not be impressed\u00a0about the amount of technology crammed into it. It compares favorably with Samsung Electronics\u2019 Q1 ultra-mobile PC, which is based on the recently launched Origami platform, and will definitely draw looks when you use it in public.At Tuesday\u2019s launch, Sony said there\u2019s also a second version on the way. This will use flash memory in place of a hard-disk drive, so it\u2019s likely to be a little lighter and more expensive. That should launch in the middle of this year.The UX50 will go on sale in Japan on May 27 and in the United States\u00a0in July. In Japan it will cost about 170,000 yen (US$1,547), and in the United States it\u00a0will cost about US$1,800, Sony said.-Martyn Williams, IDG News ServiceFor related news coverage, read Sony to Launch Blu-Ray PCs in June.Check out our CIO News Alerts and Tech Informer pages for more updated news coverage.