Easy Digital Download Points and Rewards??extension allows you to reward your customers for purchases and other actions with points that can be redeemed for discounts on future purchases.
The number of points awarded per purchase can be configured globally, per category, and even per product, giving you complete control over the reward system. Along with controlling the number of points awarded, you can set the amount that each point is worth. For example, one point could be equivalent to 1$ or 100 points could be equal to 1$, or any other ratio imaginable.
Customers can build up their point balance over time and then choose exactly when they wish to redeem those points for a discount. Customer point balances can be manually adjusted at any time by store admins.
Points and Rewards is an excellent extension for building a ???store credit??? type system. Want to reward customers for helping out in your support forums or for reporting a bug? Simply give them some points that can be redeemed on future purchases.