OK, you might not call this a deal as such and you'll have to get lucky. But...
Clearly WH Smiths are doing some great deals on PS3 and Xbox 360 games right now, and I just picked up Dead Space for £9.
However, when I paid for it, the bloke at the counter asked if I wanted to buy a couple of unboxed (but new, with manuals games) at £1 each.
He offered me Resistance - Fall of Man and Folklore which I duly snapped up. They might not be any good, but this is choccy bar prices.
So, if you live near a store then it's worth a punt I reckon. If you're lucky and they've had a few boxes lost/nicked then lurking behind the counter might be a HUGE bargain.