I know there have been a few deals on the site relating to Blockbuster Ex-rental, but found these while rummaging through the baskets yesterday. All £4 and on 3 for 2 offer.
Soul Caliber 4
Elder Scrolls: Oblivion
Kane and Lynch
They do come in the blockbuster box, without instructions. But if you just want to play the games, seems like a good deal. Scatches galore, but not a problem if your installing to HD. Will probably vary from shop to shop, but these prices have only just come in this week (Ive been checking for a while now). Bought 6 myself for £16.