"Tesco will charge £19.97 for a starter pack including a handset which when plugged into a computer will allow customers to call other users free of charge via the internet. The start-up pack sold by the retailer will include a £5 airtime voucher which can be put towards the cost of other calls. Customers will pay 2p a minute for calls to UK landlines at all times and 10p a minute to call UK mobiles, whatever the network," reports The Guardian.
Comment: The Guardian story (which has been Slashdotted) doesn't say where Tesco is getting its service, but with hindsight, that information appeared last year in The Age, in Australia, which on December 28 published a story: UK Tesco to take stake in Freshtel:
The issue follows a deal between Tesco and the Australian company under which FreshTel will provide it with a branded VoIP telephone services. "The own brand service will launch in the UK next year and be marketed and distributed through Tesco's existing retail channels," Freshtel said. Freshtel will provide the network, infrastructure and billing information for the retailer.
Otherwise the calls don't sound all that free or even cheap. I'm still using 18866 where calls from a proper phone cost 0p per minute to landlines, after the 4p connection charge.
Update: The story was covered by Richard Wray in the paper this morning.