Seems like a subscription service to pick the stores near you have coupon books printed and delivered from a site like Coupon Cabin, would be pretty cool. A rare case where the printed pages have true monetary value. Coupon Cabinsearches, aggregates and verifies printable in-store coupons from offline retail stores. Users can browse the site and find coupons for the things they need, print and use.
The site doesn't have an API (I will contact them and find out more), but it does have an RSS feed. Someone could easily pull real-time data and allow users to browse and search coupons, select the coupons they want and build book from and print one or many copies. This could be done on an individual basis or for specific locations or types of products and services. As Heath said, its definitely a rare case when the printed pages have true monetary value.