Abstract: Disclosed is a portable modular hard disk drive featuring an impact resistant case containing a hard disk drive. The hard disk drive may be mounted on a computer in such a manner that it resides on the back of, is powered by and controlled by the host computer. The invention features a like connector on its back so that additional portable modular hard disk drives may be attached to the first, powered and controlled in a like manner. The invention also possesses a belt clip for ease of carrying.