1. A non-volatile nanotube diode device comprising: first and second terminals; a semiconductor element comprising a cathode and an anode, and capable of forming a conductive pathway between the cathode and anode in response to electrical stimulus applied to the first terminal; and a nanotube switching element comprising a nanotube fabric article in electrical communication with the semiconductive element and the second terminal, the nanotube fabric article disposed between and directly and permanently electrically coupled to the semiconductor element and second terminal and capable of forming a conductive pathway between the semiconductor element and the second terminal; wherein electrical stimuli on the first and second terminals causes a plurality of logic states.