1. A non-volatile mass storage device comprising: memory circuitry remotely accessible by a host file system of a host data processing device via a communication link; processing circuitry in said non-volatile mass storage device, the processing circuitry being configured to locally access said memory circuitry in said non-volatile mass storage device as a local file system and to generate a file for storage on said memory circuitry; wherein said processing circuitry in said non-volatile mass storage device is configured to be triggered to locally access state information stored on said non-volatile mass storage device, and to dynamically generate said file comprising data derived from said state information, by connection of said non-volatile mass storage device to said host data processing device independent of said host file system of said host data processing device and without any interaction with software executed on said host data processing device, and wherein said state information comprises a combination of a serial number of said non-volatile mass storage device and a secret key generated using a hash function.