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But impressive though Phoenix is, my favourite space-borne computer predates the 33MHz CPU in the Phoenix by three decades. Voyager I, launched in 1977, is now the furthest man-made object from Planet Earth. It is very far away. On 29 May this year it was 15,917.21 million km (about 9.9 billion miles) distant. No, I'm not making that number up - those NASA chaps are nothing

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if not precise. It travels about a million miles further every day. Just for the record, it'll apparently have its first brush with a star system in around 40,000 years, coming within a couple of light years of star AC+79 3888.

And all those billions of miles away, Voyager's computers are still running and it's still communicating with us. Being built on 1970s computing technology, it carries a total of just 12KB of RAM - less than the size of the Word document containing this column. Science data is collected on a tape - a tape! - then played back via radio link to Earth every six months where NASA's Deep Space Network picks up the unbelievably tiny signal reaching us from its radio transmitter.

So that's continuous, maintenance-free operation for 30 years, without anyone to hit . If you gave me the choice of that kind of reliability on my desktop PC or transparent windows that swish on and off screen, I know which I'd choose.