Although amazon does not currently offer cashback, they do offer savings with their Daily Deals and Coupons.
Amazon puts all of its Daily Deals into a Gold Box. Rebates with Friends directs you to amazon's Gold Box page to see these Daily Deals and get limited-time savings of up to 80% off select items; You will also have access to amazon's Lightning Deals. Lightning Deals are available only for a limited amount of time and have a countdown timer showing how much time is left to get the discount. Shop before the deal expires or before the item sells out.