Ive seen that Martin Lewis bloke on TV he seems gen enough, he also does credit card tips etc.
BT also offer somthing like this where the connection number is a London based number so it is also included in your free minutes but you have to top up credit on there websitewhich means you pay BT direct rather than your operator, In which case its not like this, well.... similar, but not free. You can check it out here
