In store at Game: 50% off ALL pre-owned games from the last generation. Wii, Wii U, PS3, Xbox 360, PS Vita etc.
Games aren't labelled individually, there's just a sign on the shelves. Half the marked price. I picked up Hyrule Warriors for £4.99 and Toad for £6.50 on Wii U.
Found in Metro Centre, but the deal is nationwide.