After randomly price checking books at Kmart (Batemans Bay, NSW), I found a hardcover copy of the book 'Spin' by British author Martin Sixsmith that scanned on the price checker as 5 cents. However at the checkout, the book scanned up as 2 cents. I can't really comment on the quality of the book, (here's a review of it by The Guardian - http://www.guardian.co.uk/books/2004/apr/24/featuresreviews.…) but for 2 cents it must be worth adding to the trolley!
(Also found while randomly price checking, 'Derailed' by James Siegel - a bit less of a bargain at 50 cents)
If you take this book to the checkouts…does it mean that the book is free as 2c rounds to $0? :P