1. A promotion system supporting a plurality of user computers of a corresponding plurality of users, the promotion system comprising: a promotion collection service that receives a plurality of groups of promotion data from a plurality of independent sellers; a promotion email service that delivers to a subset of the plurality of users an email that includes promotion information related to a first of the plurality of groups of promotion data, the first of the plurality of groups of promotion data representing a sales offering of a seller; an accounting service that collects a first amount from a first user of the plurality of users, the first user responding to the email; the accounting service transferring a first portion of the first amount to an account of the seller; and the accounting service retaining a second portion of the first amount for services rendered.