Are there still parents of young children in this world that read actual paper books? If so, it would be great to know how you achieve that! Personally, if it weren't for my Kindle, I may have forgotten what anything longer than a blog post looked like. If you still read books though, this is a great offer: £1.99 books at World of Books
There are some amazing books included in this offer, and while (seemingly) second hand, are said to be in very good condition, so that's nothing to be afraid of. Better for the environment and all.
Current books that have caught my eye are Two Lives by Vikram Seth, Long Walk to Freedom by Nelson Mandela and The Curious Incident of the Dog in the Night-Time: Children's Edition by Mark Haddon. At under £6 for all three, that's a great price for long winters nights. Assuming you don't fall asleep a paragraph in to each reading session as I do these days.
If you buy one book, or 100, there's free UK delivery, with no minimum spend.