1. A portable information and transaction processing device, comprising: a central processing unit; a memory device, operatively coupled to said central processing unit, for storing transaction information comprising one of financial information, personal information, and a combination thereof; communication means for establishing a communication link with a central server of a service provider, disposed at a remote location, to download a temporary digital certificate issued by said service provider; a user interface, operatively coupled to said central processing unit, for selecting at least a portion of said transaction information; a card reader; a universal card having a unique card number designated to a subscribing user of said service provider, wherein the universal card is inserted into said card reader to receive said selected portion of said transaction information; and programming means, executable by said central processing unit, for determining if said temporary digital certificate is valid, for writing said selected portion of said transaction information to said universal card if said temporary digital certificate is deemed valid, and for preventing said selected portion of said transaction information from being written to said universal card when said temporary digital certificate is deemed invalid.