Decoding of data included in the vertical blanking interval of a television transmission signal and storage of the decoded data on a portable data coupon allows unavailable ease of use of commercial discounts, manufactures coupons, and other cost saving devices. The portable data coupon incorporates...http://www.google.de/patents/US5523794?utm_source=gb-gplus-sharePatent US5523794 - Method and apparatus for portable storage and use of data transmitted by television signal
