London Briefing/Chris Johns: A few years ago, Nobel Prize-winning economist Mr Robert Solow famously declared "I can see computers everywhere except in the productivity statistics."

He was referring specifically to the US, but his remarks were equally applicable to almost any modern economy.

The advent of the computer age was doing little to boost the underlying productivity of businesses. Stock markets ran ahead of themselves at the end of the 1990s, trying to anticipate precisely such a productivity boost. They ended up pricing in growth rates that could never be achieved, even with a technological transformation of productive potential.

Productivity determines everything; how wealthy a country becomes depends entirely on how productive is its workforce. The obsession with GDP growth rates often masks this much more important determinant of income.

Shortly after taking office, Mr Gordon Brown prioritised boosting the UK's disappointing productivity record. He has been disappointed so far, but measurement problems might be concealing an underlying rise in efficiency, with the economy now close to its potential and no sign of incipient inflation.

If growth continues to trundle along without any rise in price pressures, we will see economists - and the government - begin to herald a productivity jump. This will mean that the Bank of England can continue to raise rates at a much slower rate than they would have done in the past, in a minor replication of the US experience where strong productivity growth means the US economy can boom without any rise in inflation.

Mr Solow's original observation is showing signs of being wrong, or, at the very least, a little premature. Finally, technological change seems to have led to some fundamental changes, some improvements in underlying productivity. It may just be about lags, or perhaps the determinants of productivity growth are still poorly understood. But all those computers are beginning to make a difference.

In London, it is clear that the "unwired" revolution is beginning to make itself felt. Most coffee shops throughout the City now support wireless broadband internet access. There are many other hot spots, and vast swathes of inner London are planned to have seamless connectivity. Technology is beginning to emerge that will allow us to move around while connected, it will transcend going online in a static way in our homes or hotels.

Connecting to this new technology is actually a piece of cake, and it is easy to spot increasing numbers of people working while they sip a large espresso. And they are not just checking up on premiership football scores.

One of the issues associated with new technology and its rate of adoption is cost. It is often argued that one of the reasons why technology has taken so long to have a macroeconomic impact is that it has taken until now for prices to fall to the point where mass adoption is taking place.

Connecting to wi-fi broadband is still expensive, sometimes prohibitively so. In the Starbucks chain of coffee shops, for example, it costs £5 for one hour of connect time, or £10 for three hours. Nobody is going to simply check their e-mails at those rates.

In one of those unexpected technology paradoxes, I have discovered that it is now perfectly possible to gain free wireless broadband access in London. Somewhere near my apartment somebody has a wireless network that is not security-protected and I have discovered, quite by chance, that I can access it 24 hours a day.

I am not sure that this is legal, or, indeed, whether the law has a view on this matter. For now, I am faced with the choice of popping down to (expensive) Starbucks or sending this article via somebody else's network. Whichever method I choose, my methods of working have been transformed by technology. Once the costs of connecting fall to more reasonable levels, I suspect that the wi-fi revolution will happen.

Sceptics argue that all of this technology merely allows us to work harder and for longer. We are no longer free of the office - it accompanies us in our hand luggage. While I have some sympathy with this perspective, it is only part of the story.

The negative aspects of the digital age have been the ones stressed by the media: all that illegal downloading of music and its associated costs. But there is more to the digital age than this.

Mobile phone makers noticed, that the texting facility on handsets was extremely popular. The rest is history. The wi-fi revolution is not yet as apparent, but spend a couple of hours in any London coffee shop and you might just see its beginning.