Ms Diana Noble, the first British boss of e-Ventures, an unusual form of Internet incubator, could be said to have been recruited on Internet time.

Within two weeks of an approach by Mr Mark Booth, chief executive of e-Partners, News Corporation's new media investment vehicle, Ms Noble was installed at what is a joint venture between e-Partners and Softbank, the Japanese Internet investment bank.

Ms Noble moved speedily, largely because she had caught Internet fever while attending an advanced management programme at Harvard Business School.

In her view, the Net revolution has only just begun - and, answering charges that the Web is creaky and full of dross, says that merely underscores the scale of the opportunity.

"Only 37 per cent of US households are online and only half of those use it to buy things. Satisfaction is incredibly low - even for the best brands. If you ask where are we on the curve, it is only a few milliseconds after Big Bang."

From her new offices in Chelsea, Ms Noble will be helping US Internet companies from the Softbank portfolio build British affiliates destined for their own local stockmarket listing.

Perched among the loose cables at the former car showrooms, the first two businesses - E-Loan, an Internet mortgage bank, and buy.com, a large US Internet retailer - are getting going well before the office designers arrive.

Like many, Ms Noble is struck by how the climate is changing in Britain with the growing readiness of senior executives to leave the corporate fold. For instance, Mr Andrew Armishaw, the new boss of E-Loan in the UK, ran First Direct, the telephone bank owned by HSBC.

"Two years ago there was a stigma to doing a start-up. Now there is almost a stigma to not doing one," she says. "It's hardly surprising. As a top manager you can stay where you are and spend the next two years in strategy meetings focusing on what part of the business is capable of competing with the Net, and then issuing a stream of redundancy notices. "Or else you can build something where you go steaming over the ramparts of established businesses. It's not a difficult choice," she says.

Before moving to e-Ventures, Ms Noble spent 12 years at Schroder Ventures in London. She concentrated on buy-outs, so she has no start-up experience and no technology or operational background. What she does have, according to Mr Peter Smitham, chairman of Schroder Ventures Europe, is a "great" analytical mind. "She is very good at bringing order to disorder," he says.

Initially, e-Ventures will not be backing pure start-ups. "We don't have the resources to read a million business plans - we will be starting further up the curve. We are translating businesses that are already working in the US to the UK."

In time, it may launch US businesses other than those backed by Softbank, or even eventually UK start-ups, but the initial focus is a selection of the 110 e-commerce companies in Softbank's portfolio.

An investor in Yahoo! in the early days and now its largest shareholder, Softbank has also introduced investments in Japan - notably Yahoo! Japan. But it wanted to team up with local partners elsewhere, hence the alliance with News Corporation in Britain. On the Continent, it has formed a series of joint ventures - viso - with Vivendi, the French media and environmental services group.

Softbank's US companies are "incredibly keen" to expand, Ms Noble says. "They could do it themselves but they are constrained by resources . . . And they may need help in understanding the different nuances of the UK market."

The trick will be to benefit from the companies' start-up experience in the US. E-Ventures, which does not have a dedicated fund but is "not capital constrained", will put up roughly half the capital of the new UK businesses, with the US "mentor" company taking the other half. It will invest in the broad range of business to consumer, business to business and infrastructure Internet companies.

In true start-up fashion, plenty is still being hammered out, such as the composition of any investment committee. There is a weighty board, including both Mr Masayoshi Son, founder of Softbank, and Mr Rupert Murdoch, chairman of News Corporation and, until fairly recently, a notorious bear of the Net. But no one seems to have decided who will be chairman.

Meanwhile, the pressure is on to get the team in place. "We have to gear up sufficiently quickly to ensure we are not a bottleneck," as Ms Noble puts it.