Tesco are selling the ITD68 Freeview Digibox from Sagem for £7. It's not the best digibox in the world, but for £7.00 it seems like a decent way of getting Freeview on your telly. These are definitely in stock at Bolton, and should be the same price at other stores too.
Look for them in boxes with ESPN on them since these are Top Up TV capable - though I don't think anyone's even interested in the on-its-way out Top Up TV. You're best off just using these for standard Freeview.