Amazon's Giveaways website is exactly what it sounds like: It's a page where you can enter to win the products posted on the website. But even if you're not chosen, you can still snag the product at a discount.
When browsing Giveaways, you'll notice there's a discount listed for most products. If you've entered the giveaway and have been notified that you didn't win, click the "Add to Cart" button to claim the deal. The discount will be applied at the last step of the checkout process, similar to how coupons work on Amazon.