see also Multi-Level Marketing. A scheme in which a person (as a "seller") buys a certain amount of product from a "distributor", and then sells for a profit. The seller must then kick back some of his profit to his distributor. In turn all the other sellers this person has recruited and distributes product to must kick back some of their profits to him.
Amway is the prototypical MLM. Usually only the founders of a MLM profit from the scheme. Some MLM's are blatant pyramid schemes, although one can argue all MLM's are fraudulent. Look for MLM ads in bus shelters and on telephone poles at intersections.
I just blew my inheritance from Grandma on this Flowbee MLM!