I went to my local Wyevale today (Hemel Hempstead) and they had a huge table full of packets of vegetable seeds which were reduced to 50p per packet. I was told this is a nationwide offer.
There were lots of different brands to choose from including Thompson & Morgan, Suttons and Duchy Original and they have been reduced from as much as £3.49! Most of them are dated to be sown but August 2012.
You have to be a Gardening Club member to buy them at this price but it's free to join.