Did you know that if the price on something you buy drops, within 30 days of your purchase date, Amazon.com will credit you the difference if you ask for it? It's a not-advertised price drop policy that most people don't know about and it's saved me tons of money over the last few years. I didn't know it was "secret" until I brought up recently and no one knew what I was talking about, so I thought I'd write a post all about how to take advantage of it. One of the great things about the drop policy is that it still works for orders where a coupon is involved or a "Buy Both and Save" deal is utilized. They only consider the individual item prices (based on the invoice) and not the final price after discounts!
I'm sure the reason they don't hype it is that they don't want people to use it. But I think it's a big reason to buy from Amazon and they should promote it.