1. A three-dimensional nanoscale electronic device comprising: a first functional layer including nanowires and a first type of nanowire junction; and one or more additional functional layers, layered above the first functional layer, including nanowires and one or more additional types of nanowire junctions, the first functional layer and one or more additional functional layers interconnected, in a direction approximately normal to planes of the first and one or more functional layers, through one or more of nanowires, nanowire junctions, microscale signal lines, and submicroscale signal lines.