Wow!!!   
Walgreens has Pepsi Products 4 for $12, and get a $3 Register Reward.


Roll (for rolling see coupon lingo) this deal now you can use the $3 Register Reward to buy 4 more.


Scenario
Buy (4) 12 pack of Pepsi $12, get the $3 Register Reward
In another transaction buy (4) 12 pack of Pepsi Products  = $12 - Use $3 Register Reward = 4/$9
Receive another $3 Register Reward
You can continue to "ROLL" this Register Reward for Pepsi!