Abstract: A “swipe”-type magnetic stripe reader suitable as a low-cost computer peripheral is described, together with distribution programs to create incentives for the wide deployment of the readers. The readers are used in conjunction with methods for distributing, through print media, machine readable, magnetically encoded media that may be read with the readers. An optional authentication mechanism may be built into the readers that can be used to control their use, based on information encoded into the machine-readable media that have been distributed. The encoded authentication information can, for example, be keyed to whether an advertiser has been authorized, and/or based on temporal criteria, so as to provide for effective time periods for a promotion.