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 conductive terminal; and a nanotube switching element comprising a nanotube fabric article in electrical communication with the semiconductive element, the nanotube fabric article disposed between 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.