If you do a lot of shopping on Amazon, and you use Firefox, you should look at using the Buylater plug-in for Firefox (http://buylater.cognition.ca/). With Buylater when you are shopping on Amazon, it adds a button to pages so that you can keep track of items. It's kind of like an Amazon-only bookmark, but it has added benefits. If the item is out of stock, you can choose to get notified, via email or Twitter, when the item is back in stock. You can also use this to get notifications of price changes. So if you are waiting for an item on Amazon to come down in price, you don't have to keep going back to check the price, you'll get notified immediately once the price drops.