The founders of the Skype internet telephony service are launching what they describe as the world's first broadcast quality internet TV service.
By Rory Cellan-Jones
Technology Correspondent, BBC News
Following speculation about a service dubbed The Venice Project, the online television software is now being unveiled under the name Joost.
It is designed to enable broadcasters to get their programmes in front of a global internet audience.
It will allow viewers to access all kinds of television over the internet.
The chief executive, Frederik de Wahl, showing off the service in Joost's London offices, claimed that it provided a different experience from other internet television ventures.
"We are trying to replicate the complete television experience," he explained as he flicked through channels using the Joost interface on a widescreen television.
"It's full-screen, broadcast quality, you've got instant channel flipping, and interactivity - a viewer can come to us and get all their TV needs."
The service is still undergoing trials, but thousands of people have taken up an invitation to download the software and try it out.
But the big question is what is there to watch?
So far, it is hard to see a compelling reason to switch on to Joost, which will be a free service supported by advertising.
There is a line-up of sports, documentaries and music programming, but nothing that is going to tempt many away from their existing television diet.
But Mr De Wahl insists this is just trial programming and when the full launch takes place in the next few months there will be much more impressive content on offer.
Joost is backed by Niklas Zennstrom and Janus Friis, who founded Skype, while Frederik de Wahl previously ran a business whose peer-to-peer software was used in Skype.
He says a version of that software is key to the appeal of Joost, with new peer-to-peer technology, backed up by the firm's own servers, making it possible to stream video on demand.
But rival services are already casting doubt on the claim that Joost represents a new frontier for internet television.
BT Vision, launched in December, offers video-on-demand via broadband, and Channel Four Television says its 4OD service promises DVD-quality programmes to download to your computer.
Meanwhile another company calling itself Babelgum contacted the BBC to insist that its service, launching in March, would also use peer-to-peer technology to stream video at "near-TV resolution".
A spokesman said "the Venice Project hasn't got this to itself."
The battle to broadcast over the internet is hotting up and the Venice Project - or Joost as we now must call it - will have to make plenty of noise to make itself heard.