Google offers discount coupons to Google Maps users:

“Google will offer printable discount coupons to local shoppers, in a promotional bid that aims to drive U.S. online shoppers using its Google Maps service to visit stores….Google is taking advantage of the marketing tool, which is traditionally used by small businesses, to entice U.S. consumers to seek out savings from local retailers such as dry cleaners, pizza delivery restaurants and auto repair shops. Google has partnered with Valpak, the top U.S. supplier of coupon advertising, to provide more than 20,000 coupons from current Valpak advertisers when consumers search for relevant stores using its Google Maps map and local directory service.”