O2 offers BlackBerry Curve 8520, Bold 9700 and more on pay as you go

O2 is offering five BlackBerrys on pay as you go, making it easier to get your hands on a smart phone without signing up to a long contract. Cynics among you might say it's also a good way for the network to clear old stock and make way for new BlackBerrys.

The devices on offer include the BlackBerry Curve 8520 in black or purple for £150, the BlackBerry Curve 8900 for £280 and the BlackBerry Pearl 3G 9105 in purple or black for £250. At the moment, only the Pearl 3G and the 8520 are available online.

Not widely promoted is the fact that the BlackBerry Bold 9700 is available on pay as you go for £350 and the BlackBerry Storm 2 for £400. If you compare these prices with that of the unlocked iPhone 4, available for £500, you might not think this is such a great deal.

If you're thinking of buying one of these phones on pay as you go, bear in mind the Bold and the Pearl 3G will be the only devices retrospectively compatible with the new BlackBerry 6 OS. If you're looking for a classic BlackBerry with up to date software, but don't want to be tied into a contract, these could be a good deal.

Rival network T-Mobile is doing exactly the same thing with the BlackBerry Pearl 3G 9105. This comes just as RIM has finished showing off the BlackBerry Torch, with other new phones on the horizon. 

With T-Mobile and O2 deciding to turf their old BlackBerry stock, it will soon be time for other networks to follow suit. There are no details yet on whether a new BlackBerry range of devices will be available on pay as you go. Networks have been cagey about this in the past, especially because trapping you in an 18-month or two-year contract is much more profitable.

Apple may have opened up the floodgates of contract freedom by offering the iPhone 4 unlocked for £500. As a result, many networks are being forced to offer smart phones on pay as you go to match Apple's relatively competitive pricing.