Each week Publix has a store brand mystery item on sale for a penny with each $10.00 purchase. This item is only on sale every Sunday and Monday. Generally you don't even need a coupon (it's in the ad), but ask at the Customer Service Counter to make sure. At the store by my house, it automatically rings up at one penny.
This week - 5/3 & 5/4 - Publix iced tea half gallon