A few personal technology products are so well designed and engineered that they set the benchmarks for all others. Devices such as Apple’s iPod family, including the new iPod Touch, RIM’s BlackBerry smartphones and TomTom’s satellite navigation devices share some key qualities: they are simple to use, do one thing superbly and are still reasonably priced.

Arguably, the Sonos Digital Music System – an expandable “whole house” wireless digital music system – deserves a place in this elite group. Sonos (www. sonos.com), a California-based start-up that was founded by music enthusiasts, delayed the launch of its first products a few years ago because it was dissatisfied with the manufacturing quality of some components. When the system finally became available in the US in early 2005, it was greeted with critical acclaim.