Where is the logic in this? After over a year of putting up with my mobile phone (a Motorola Timeport 250) I've decided it's time for a new one. I'm with T-Mobile, so I was pleased to see the big signs on the windows of Carphone Warehouse telling me that the phone I want (the Nokia 8310) is now free.

And it is free, but only on new contracts. To upgrade on an existing contract, keeping the same phone number, it's £129.99. If I switch to a new network, I get the phone for free and I can keep my number. So it's bye-bye T-Mobile. The future is Orange

I called T-Mobile and told the customer service guy I needed my 'PAC number', as I was switching to Orange. "Hold on," he said, and put me on hold for ages.

"Hello, this is Geraldine. I believe you're thinking of leaving T-Mobile? You want the 8310? Well, allow us to buy it for you. Yes, free. Just get Carphone Warehouse to fax us the proof of purchase, and we'll refund your account immediately. Oh, and the price plan you're on: are you sure that's the right one for you? Why don't we switch you to this cheaper one? Oh, and I'll throw in 50 free text messages per month."