The silly thing about this is that I've had this data the entire time. I simply never displayed it. But now it's available for your viewing pleasure!
When looking at a particular item, click on "Price History" to see how today's price stacks up against historical pricing at Amazon. Maybe it's the best deal yet! Or maybe you should wait a few days for it to drop back to a normal/lower price.
Here's a good example (for a toy that I highly recommend)! The historical pricing for the Duplo Modular Dollhouse (which my kids love). As of this post, it's at its best price ever, so there's no point in hesitating to buy!