This parallel economy could be a model for Tony Blair

We have inner cities packed with people who have time and skills available, surrounded by tasks which desperately need doing - but no cash to bring them all together

The fearsome Alan Greenspan took over the US Federal Reserve 10 years ago this month, and it has been - if you believe Fortune magazine - "10 of the best years in the history of monetary policy". Newsweek, meanwhile, has been praising US Treasury Secretary Robert Rubin as "the best in memory".

There are no two ways about it: although they look nervously at their sky-rocketing share index, many Americans really think they have finally got the economic problem licked.

It depends how you work it out of course. If you measure the gap between rich and poor children, for example, the USA would be 18th among 18 industrialised countries. Or carbon emissions, or energy consumption per head, or number of children killed by gunfire. Indicators - even the strictly economic ones - are particularly ambiguous when it comes to the US.

The strange thing about modern economics is the way abundance tends to rub shoulders with serious need. Mr Greenspan's economy includes Bill Gates - who is $18bn (pounds 11.25bn) richer than he was a year ago - as well as Memphis, where one in 23 households are bankrupt.

But then the UK economy does the same. You can find empty hungry people in any British city, or desperate summer sales to get rid of surplus stock which remains beyond the pockets of most of the population. We have British inner cities packed with people who have time and skills available, surrounded by tasks which desperately need doing - but no cash to bring them all together.

We have long ago solved the problem of production, in other words, and we have yet to manage the problem of distribution.

But one idea from an American city might show us all a way forward - if it works. The Commonweal project in Minneapolis aims to find a way of linking over-production with the people who need it most. It is the brainchild of former political activist Joel Hodroff, and it launched its pilot programme in the Minneapolis inner city neighbourhood of Lyndale in April.

It works like this. Jane, an unemployed carpenter, does some work for a charity or local agency which can't afford to pay her in dollars, but can afford to pay her in "service credits" - a kind of voluntary sector version of Air Miles.

She can use these in a range of restaurants, shops or on other services around the city which have agreed to take them - usually at off-peak times. So a restaurant which has to employ cooks and waiters and heat the place all afternoon for the benefit of a handful of customers, can fill their tables for service credits plus enough dollars to cover their costs.

The businesses signing up include Camp Snoopy, the theme park in the middle of the gigantic Mall of America, the biggest shopping mall in the USA, just outside the city - Charlie Brown happens to be from Minneapolis. Camp Snoopy has to stay open through busy Saturdays as well as quiet Wednesdays.

They can clear their excess stock without expensive marketing, but at the same time the businesses are underpinning a parallel economy where people can "earn" for doing the kind of community tasks the government now seems unable to pay for itself.

It is early days yet for Commonweal, which was launched with the backing of the local council, a couple of local banks and some big thinkers like Alvin Toffler and Paul Hawken.

There are too few participants yet to launch their patented dual-track credit card known, rather self-consciously, as the "Community HeroCard".

"But we are using the world's first dual-currency service slips," says Mr Hodroff with enthusiasm. "It is going well, which means we are finding it easier to talk to major banks and retailers about taking part."

If it all works out, it could be a bonanza for Commonweal - they take a percentage of each transaction, like a credit card company - but it could also be an interesting new model for Tony Blair, and other politicians looking for new ways of unleashing the support of volunteers while their budgets shrink.

The options before most governments these days are pretty meagre to get local needs met. They can print more money - but that would cause inflation and scare the international money markets. They can cut the budgets and hope for the best, but then they get voted out of office.

The Commonweal idea is to use the economy's manifest over-capacity to put purchasing power in the hands of people who don't have it at the moment.

"We have work to do, we have plenty of people with skills, we have sufficient technical and management capacity, we even have adequate energy and raw materials. The only thing that's getting in the way and preventing that work from being completed is a lack of money," says Mr Hodroff. "That's absurd. Money was created to promote economic activity, not to inhibit it. We have outgrown the old scarce commodity money and it is time to introduce something new."

Commonweal's credits are a new twist to the phenomenon of computer money, which - unlike pounds and dollars - is infinite.

Air Miles or Sainsbury's Reward points are limited only by the cashflow and productive capacity of the company issuing them, and because they don't want to be overwhelmed. They come from nowhere and, when they are spent, they don't go into the bank vault - they just get deleted.

Private sector finances like these do not circulate in the traditional way. They exist to encourage people to act in a certain way - normally to buy more. So why not invent some corporate "money" which encourages people to get active in the community.

The idea of "service credits" or "time dollars" paid to volunteers has become a familiar aspect of American life, though it has yet to catch on in the UK. You can earn them in well over 100 US cities now - but Commonweal is probably the first time big business has been involved in the idea.

But if they want to offload surplus stock in a useful way, Commonweal needs to tackle poverty. "Participation will be totally voluntary," Mr Hodroff says. "But my guess is that people will flood off welfare to earn 10 community service dollars per hour."

It is early days yet, and many people might prefer welfare. You don't, after all, want to build a second-tier economy for poor people - palmed off by participating businesses with their second-rate stock.

It is a legitimate concern, but Commonweal is an exciting idea. If Tony Blair wants to find ways of regenerating the social capital lost over the past generation, this might be a good place to start looking.