As someone posted on here recently, Independence Day Blu-Ray was seen in-store at Tesco for only £3 - bargain! However, now with their sale on, I picked this up BOGOF, £3 for two copies. This is only £1.50 for a great (if cheesy blockbuster) film!!! Next best price I can see is £9.85 at Zavvi.
I think this is a mis-price as it is priced £20 on the box but priced £3 + BOGOF on the sticker and scanned as such. As there was another post about the £3 deal recently I believe this is available nationwide.
This was at the store in West Byfleet. There were still another couple of copies left on the shelf.
Other bargains include:
A History of Violence £7 (next best price is £8.85 at Zavvi/The Hut)
Flags of Our Fathers £7 (next best £9.85 at Zavvi/The Hut)
Various on BOGOF for £15, also Slumdog Millionaire £25, BOGOF (out of stock at most other shops I've checked)