Was searching on Play.com for a specific book (http://www.play.com/Books/Books/4-/395901/Introduction-to-Project-Finance/Product.html), and when I went to the product page the item was stated as available for £0!!
I got really excited, added to shopping basket, and the shopping basket still said £0 delivered. However, after clicking checkout, the price reverted back to the original £23.99.
Could this be play.com using a dirty tactic to fool price comparison websites or get customers to unwittingly buy at a higher price, as some customers might not double check the price?