If you’ve ever spent a long time going back and forth about a possible purchase on Amazon, then you’ve likely noticed that, without warning, the price of that item can change. This is by design. From Quartz, Amazon changed the price of the Bible over 100 times in five years. (I’m loading my shopping cart with books by Bill Maher, Richard Dawkins and Chris Hitchens just to see how low I can get the price…)