1. A method in a data processing system for automatically initiating the replenishment of a consumable product, comprising: on a first date, fulfilling an order by a consumer for a first instance of the product; based upon the first date, estimating, by a computer processor, a second date by which the first instance of the product will be fully consumed, wherein the second date is based at least in part upon a replenishment time interval between prior purchases, each of the prior purchases including at least one purchase of a complement of the consumable product; before the second date, providing to the consumer an indication that the product should be replenished, the indication including a control usable by the consumer to request replenishment of the product by performing a single action; receiving an indication that the control was used by the consumer to request replenishment of the product; and in response solely to receiving the indication, ordering a second instance of the product to replenish the first instance.