All machines are always in tip-top condition, with enough RAM to allow the simultaneous operation of between eight and 15 applications. They also have the intelligence to flag memory and operating stress by changing the desktop screen colour from deep blue, to light blue, to light green, to light pink as a crash point is approached. Once running they are left operational with, at worst, just the monitors switched off. By any reckoning I consider this to be a pretty slick set of powerful and stable systems.

Well, of course these machines do crash. All systems do, it is something we seem to have to live with. But on average, when everything is behaving itself, I have it down to once in three or four weeks. So I guess I had every right to feel smug when listening to the woes of others, with three or four crashes a morning.

However, a new pair of hands arrived, in the shape of a colleague collaborating in an experiment who required direct access to my machines. With bravado I explained how good my systems were, how solid and reliable, and how well I looked after them. "Just get to it - you cannot possibly upset my computers."

To my astonishment he was in multiple crash mode within 15 minutes. Applications and operations that would run faultlessly for me presented a trail of grief for this newcomer. What was happening?

It was if I had some secret symbiosis with these computers and the stranger did not. Surely my machine was not smart enough to tell us apart and then inflict some secret trial by crash on my colleague› Well, not quite. However, as far as I could tell I had been quietly tutored not to touch the mouse when my browser was doing its stuff, to avoid doing much at all when sharing my hard disk with others, and so on. I had been subject to a subliminal process of conditioning by my machines, and perhaps I had not been so smart after all.

Over a few days, a week, a month, my colleague gradually gained the acceptance of my machines and his crash rate gradually fell to twice a day, once a day, once every couple of days. Here he reached a plateau of stability, and unfortunately came to the end of the experiment.

He never did achieve my enviable condition, and left me slightly concerned. Just how do I do it? Is operating a computer really like playing a musical instrument? Is our technology becoming much more sentient and tuning us to it's foibles?

Moving to my laptop, which is only a fraction of the size of my other machines, with a drastically runed down operating system and application set, I decided on a rematch. The same colleague moved into my crash league almost instantly. In fact, it turned out to be very difficult to crash this system - and when it happened it was through a pattern I recognised. So perhaps we do enjoy a symbiosis with computers that gets ever more critical and interesting with size and complexity.

Peter Cochrane holds the Collier Chair for the Public Understanding of Science & Technology at the University of Bristol. His home page is:
http://cochrane.org.uk