RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
ReviewsOffers.com - ReviewsOffers.com is online coupon community forum. Also you can share your shopping experience. Find latest coupon code, deals and discount offers.
Dealspotr - Dealspotr is like Wikipedia for deals.
Briefcase by AppSumo - "Netflix for software"
Groupon - Each day Groupon offers a deal through local vendors in your city.