A computer-readable medium containing instructions, which when executed by an electronic appliance, are operable to cause the electronic appliance to perform actions including the following:
- receiving
- (1) a secure digital container including a file and information steganographically-encoded into the file, and
- (2) a first control set made up of at least one control;
- opening the secure digital container to retrieve at least a first portion of the file, the step of opening being at least in part controlled by the first control set;
- and
- recording information relating to the opening of the secure digital container, the recording occurring at least in part under control of the first control set.