A printed wiring board including a conductive layer, the conductive layer including a network of nanotubes with respective longitudinal axes, the nanotubes arranged such that their longitudinal axes are aligned substantially parallel to one another in a configuration such that electrical current passing through the conductive layer along a first axis substantially parallel to the longitudinal axes of the nanotubes experiences one degree of dissipation, and electrical current passing through the conductive layer along a second axis experiences a higher degree of dissipation.