Just back from Tesco and they had a few blu-rays at £5. I picked up Edge of Darkness, and although stickered at £5 came up at £8, but the price was adjusted. Not sure if some dunce has stickered them all up wrong at this particular store or if some of the others come up at £5. I might go back in a bit, pick up a pile and go to the price checker machine.
Other discs I spotted included
Aliens Vs Predator (£8.99 on Amazon)
Lord of the Rings - Fellowship of the Ring (£6.99 on Amazon)
Lord of the Rings - Return of the King (£6.99 on Amazon)
Was a few others but can't recall them with any certainty.