A portable non-volatile memory device including a user interface for selectively assigning one of a plurality of security statuses to a user file stored therein is provided. In some embodiments, the memory device includes a power source so that the user interface is operative even when the memory device is in an uncoupled state. Optionally, the device provides a mechanism for authenticating users. In exemplary embodiments, the assigned security status of a user file is selected from the group consisting of non-secure, encrypted, visible while protected against copying and hidden.