A transaction card includes a housing, a first roller, a second roller and a machine readable link. The first roller is rotatably coupled to and at least partially stored within the housing and has a first rotational axis. The second roller is rotatably coupled to and at least partially stored within...http://www.google.fr/patents/US7861926?utm_source=gb-gplus-shareBrevet US7861926 - Transaction card with movable member
