Sorry to be that guy, but isn't there a huge legal issue? In France, the CNIL requires a declaration of any file, especially if you keep information about people in it, whether it's a spreadsheet or in good old punch cards. Such files can only be maintained for specific purpose; notably keeping tabs on what people want or their secrets can be used for bribes and leverage. An Excel file on your computer won't get you arrested because of leniency, but if we start issuing such software, the defense is less solid than for Torrent software.
i.e. What happens if a database is leaked?