1. A removable digital data storage device, comprising: a programmable memory controller encoded with a firmware program; a data storage medium coupled to the controller; and a data destruction means in communication with the controller and coupled to the medium; wherein the firmware program is configured to cause the programmable memory controller to function as a device driver interface to a first computer; and wherein the firmware program is further configured to cause the memory controller to query for a first hardware code in response to a data operation request by the first computer on the medium through the interface and either: grant the first computer access to the data storage medium through the interface in response to a first hardware code input through the interface; or independent of an operational status of the first computer directly instruct the data destruction means to render data residing on the data storage medium unreadable in response to a failure to receive the first hardware code input through the interface.