By the way, if you already have a Virgin Mobile account (whether it's PAYG, Contract or whatever) you can get some great deals on handsets with them.  If your PAYG number is un-registered, it'll need to be registered first.  If it's never been registered before, you're better off registering the number yourself on their website as this will generate a £2 reward which you WON'T get if you ask them to register it for you over the phone. Virgin are the only network that will unlock a handset free of charge - as long as the phone came from them in the first place.  The only other stipulation is that you must have used £30's worth of airtime on the mobile number in the time you've had it for each phone you want unlocking.  They send you a letter with the unlock code in it with full instructions for unlocking it. Even if you only use your Pay as You Go Virgin phone occasionally, I'm sure you must have used £30 on it during the time you've had it, assuming you've had it a while and you've not ordered an unlock code from them before!  Call 789 from your existing Virgin Mobile number and ask what handsets they have available - tell them you don't want a SIM though and you just want to buy a phone on its own. 

They also sell re-conditioned phones that are half of the price of a new handset of the same model, but they only give half of the warranty.  For example, a phone that costs £80 new with a 12 month warranty would cost £40 re-conditioned with a 6 month warranty.  You could buy an inexpensive phone from Virgin, get it unlocked and use an Asda Mobile SIM in it (see my previous post!)  Good luck!