Christmas promotion for employees

From the day after Thanksgiving until the end of December our bank offers our employees what we call 'Santa Bucks'. For each dollar we spend in our local area, the bank gives us .10, so if we spend $1000. we end up getting $100. We are trying to "jazz it up" this year. We already have a bonus for the person who turns in the most slips, and a bonus for the person who goes to the most different places. We thought about maybe getting the local merchants involved. Any suggestions?