It's not often you see Microsoft trumpeting how proprietary its technology is, but the sales pitch for its forthcoming BlueTrack mice is that you won't be able to get them from anybody else. And the reason you might want one is that BlueTrack outperforms the old laser technology and works on almost any surface. It's "the four-wheeled drive of mice," says the designer. It will, apparently, work on your wood, granite or marble worktop, and on your thick-shag living-room carpet -- there's a video with the inventor. More importantly, it will work on airline tray tables. It won't work, not surprisingly, on glass and mirrors.

Channel 10's Laura Foy has an enthusiastic video report, Microsoft Unveils World's Most Advanced Tracking Technology. Bear in mind that Channel 10 is owned and operated by Microsoft. It's not CNN.

Two new BlueTrack mice, Explorer and Mini, will go on sale at Best Buy in November for the estimated retail price of $99.95 and $79.95 respectively. In the longer run, you can expect BlueTrack to replace the lasers in most other Microsoft mice, depending on price.