Virgin Media's new Big Data pay-as-you-go SIM may tempt a few of you, as it sees the network offer unlimited mobile data to SIM-only customers in return for topping up with £10 of credit a month.

If you add £10 of calling credit Virgin Media then also shovels 300 SMS messages and an unlimited data bundle to your SIM, with a £15 top-up boosting the SMS allowance to unlimited status as well. All you have to do is buy a standard Virgin Mobile SIM and wait a month, when you'll be able to call its people and have your plan changed to the Big Data option.

Virgin uses EE's combined Orange and T-Mobile service for its coverage. So if you get a good EE signal Virgin's super-cheap data SIM would do, although you'll pay by the minute for your calls, so it would suit the less sociable type. [Virgin Media]