Just been to my local Waitrose (Sheffield) and they were reducing a number of toys by large amounts.
I picked up a Barbie Singing Island Princess for £1.50 (down from £8.50!) and a Kid KNEX puppy set for £1.99 (down from £7.99) They also had a Penguin KNEX set for the same amount.
They had another Barbie Island Princess for £2.99, some Playmobil sets and a make your own bracelet type set. I didn't see how much these were I'm afraid.
They were in the middle of reducing them as I was there so there may be other things added to the list! These would make lovely cheap presents for childrens birthday parties!