1. A molecular crossbar latch comprising two control wires and a signal wire that crosses said two control wires at a non-zero angle to thereby form a junction with each control wire, wherein each junction forms a switch and each said junction has a functional dimension in nanometers, with said signal wire selectively having at least two different voltage states, ranging from a 0 state to a 1 state, wherein there is an asymmetry with respect to the direction of current flow from said signal wire through one junction compared to another junction such that current flowing through one junction into or out of said signal wire can open or close, respectively, said switch, while current flowing through said other junction out of or into said signal wire can close or open, respectively, said switch, and wherein there is a voltage threshold for switching between an open switch and a closed switch, said latch further including a control mechanism for controllably electrically connecting and disconnecting signal input to said latch, thus allowing said input to change said logic value after said signal is latched while said signal wire retains its latched value.