According to the invention, an electronic data storage cartridge for removable coupling to a computing system is disclosed. The electronic data storage cartridge includes a cartridge body, a connector, an optical waveguide, a hard disk drive, and a mechanical write-protect switch that prevents modification of information on the hard disk drive when active. The cartridge body includes at least two outer surfaces. The connector can be used for removable coupling to the computing system, where the connector couples information outside the cartridge body. The optical waveguide is configured to couple light between the two outer surfaces. The hard drive is coupled to the connector.