With the announcement this morning that 3 and Skype have teamed up to offer free calls to mobile phone users when they are on the 3 network, should mobile phone operators be worried that this move will change the industry forever?

"There is resistance from some operators to include the software", Michael van Swaaij, acting CEO of Skype, told us.

After all, the main way a mobile phone operator makes money is not by the sale of the handsets but encouraging people to make more calls. Take that out of the equation and you start to wonder where the profits will come from.

That's why 3 is not only making a bold move, but one that many operators wouldn't have the courage to make. They are trusting that their customers will want to use the 3 network beyond the no-cost Skype offering.

3 believes that it can make enough money through incremental sales of other voice calls.

But are they right to believe this? Well I think they are. It might only have been launched this morning, but already I've contemplated the idea that for my office - all working remotely - it might be the best and cheapest solution for me and my team to stay in touch.

Okay, so some will say that the offer is merely a network giving thousands of spare minutes and that it's no big deal, but the move to greater interconnectivity between PC and mobile is just the first step.

This is, as Skype's CEO says "Skype in your pocket" and moves the world towards just one username to remember.

How many identities do you have? Probably a lot, I have certainly got a mobile, landline number, then there is my MSN sign-in, my AOL sign-in, my Yahoo sign-in, My Skype sign-in. One number to rule them all would work well.

But there will be limitations, it's early days at the moment, there is no SkypeOut, no video calling and no roaming outside the 3 network.

However this, along with the idea of a phone that will allow you to connect for free to Wi-Fi hotspots around the country, can only make communicating easier, as well as cheaper, and I am all for that.