In a preferred embodiment, a flash card unit, including: a housing; receiving means to receive in the housing a flash card having thereon at least first and second graphics; illuminating apparatus disposed in the housing to selectively illuminate at least one of the first and second graphics; the first...http://www.google.de/patents/US6463258?utm_source=gb-gplus-sharePatent US6463258 - Electrical flash card unit and method of use
