CALL it the Skype economy. The creators of the internet-telephony sensation that was sold to eBay for $2.6 billion (£1.3 billion) – or 40 times its 2005 revenues – are ploughing their millions into a plethora of new start-ups.

In Estonia, where the London-based Skype employs about 250 people, the company’s senior software engineers have set up Ambient Sound Investments to back technology firms from the Baltics.

Ahti Heinla, Priit Kasesalu, Jaan Tallinn and Toivo Annus are investing in everything from satellite communications to cancer therapy, from vehicle-tracking to English-language teaching for the Chinese.

“It’s fine to rethink the metal thingie inside some plastic whatchamajig,” says the manifesto on Ambient Sound’s website. “But it’s just not our cup of cappuccino. What we really want to do is change the world.”

Niklas Zennström and Janus Friis, the Scandinavian duo who founded Skype, could not have put it better themselves. Having caused havoc in the music industry with Kazaa, the song-downloading service, and shaken up international telephony with Skype, they are also looking at new opportunities.

“I am an entrepreneur in my heart,” said Zennström during an interview at Skype’s fancy offices in London’s West End. “I want to build things.”

While continuing as chief executive of Skype, Zennström has set up his own investment company, Atomico, run by fellow Swede Mattias Ljungman. Atomico’s portfolio includes Fon, the wifi-sharing business, Last.fm, a music service, and wunderloop, which has developed technology for better targeting of online advertising.

Zennström said Atomico was interested in entrepreneurs in his own mould – “who have very big ambitions, have an opportunity to change something and be disruptive in some way, and [businesses] that can scale”.

Kazaa and Skype, two of the most widely downloaded programs of all time, certainly fit this description. Kazaa’s success in enabling the free sharing of digital music by millions of people attracted a legal onslaught from the recording industry. Although Zennström and Friis were not personally charged – they had sold out and moved on – they had to stay away from the US until the Kazaa litigation was settled for $115m last year.

Skype now has nearly 200m users, having more than doubled in size during 18 months under eBay’s ownership; it has just made its first profits and is on course to generate more than $400m of revenue this year.

Zennström said the relationship with eBay was “very good”, though Skype has become more focused on hitting its financial targets – not least because he and other vendors have $1.2 billion of earn-out payments riding on the firm’s performance over the next couple of years.

Nonetheless, Zennström and Friis are trying for a hat-trick of successes with Joost, their new internet TV venture, due to launch shortly.

Zennström said: “We want

to change the way people watch television with a very smart new technology, and make the service much better than traditional television – liberating people from the programme guide. We are taking away the limitations of the number of channels.”

More important, though, will be the availability of something good to watch. The fledgling firm has been able to agree deals with media giants such as Viacom, which owns MTV and Comedy Central, and CBS.

“The media industry is very much in synch with the internet players in terms of what they want to do online,” said Zennström. “A few years ago, technologists were much more ahead of time – that’s why there was so much litigation. Those frustrations have gone.”

Certainly, the entertainment industry is fixated on the potential for transmitting video, on demand, over a broadband internet connection.

The huge popularity of YouTube, now owned by Google, has demonstrated the strength of consumers’ appetite. Apple’s iTunes and the e-tailing giant Amazon both have services that could develop into destinations for online video.

And News Corporation, the ultimate owner of The Sunday Times, is working with NBC to make movies and TV programmes more widely available through Yahoo, MSN, AOL and MySpace.

Zennström is unfazed by the heavyweight competition. He said: “My experience is that when there’s a big change happening you’re much better off starting from a blank sheet of paper than with a big installed base of customers.”

Joost intends to make money in a traditional way, from advertising. On Thursday, it announced an extremely impressive list of 32 advertising launch partners, including Coca-Cola, Nike, Intel, Vodafone, Sony, Microsoft, Procter & Gamble, Unilever and General Motors.

Coming after Kazaa and Skype, Zennström said that Joost was “very different because I am not the one who has to make it work”.

While Friis has spent much of his time on Joost, the company’s management team is headed by Fredrik de Wahl.

“There’s a lot of growth with Skype,” said Zennström. “I am committed here for some time.”

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