Automatically create groups of customers based on a Customer's total sales in the last XX period, and give bonuses based on their spend. For example: Customer who has spent $100 in the last year gets put into level 1 and receives an email for $20 off next purchase (no coupon code needed), Customer who spends $500 gets level 2 and gets free shipping for the next year (automatically gets email telling them they reached that group, when the end date is, shipping automatically deducted, no coupon code needed - removed from the list if/when they fall behind on the $500 in last 365 day threashold)