Go to Whataburger and buy any item at regular price. Do the survey on the receipt (very easy) and write the number given at completion on your receipt. This earns you a free Whataburger with the purchase of a medium fry and medium drink. Total cost for this lunch in Jacksonville TX is $5.39 (sandwich,fries,drink). Repeat as often as you like. Deal is good for 30 days after you take the survey at any Whataburger restaurant.
No Whataburgers in South Florida. The nearest one is St. Augustine. After gasoline and tolls I wonder how much that discount would end up costing me?