Adam Viener of ReveNews.com discovered a Yahoo! Shortcut which gives searchers quick and easy access to coupon codes.
This is a great service for consumers who are spared the trouble of weeding through creatively written sponsored listings and pages of organic listings claiming to have the best coupons and then returning out of date deals. This is also a potential win for Yahoo! as affiliate revenue can add up pretty quickly.
The comments on Adam's post seem to indicate that the coupons are sourced through a third party called Coupon Cabin, but there's no confirmation of that. Last year Yahoo! tested out a different partner for coupons on Yahoo! Shopping.