Wikibuy - Find lower prices at other sellers while you shop on Amazon
RetailMeNot Genie - Instantly apply the internet's best coupons at checkout
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
Dollar A Day - Automatically donate $1 a day to featured nonprofits.
CouponFollow Cently - Coupons at Checkout is a browser plugin for Chrome, Firefox, Internet Explorer, and Safari that...
Shopper.com - Uber for Coupon Codes