Polymer electronics often enough use metallic or metal oxide conductors as contacting materials. This article at PNAS discloses a solvent annealing process to enhance the electrical conductivity of polymers like polyaniline to levels adequate to replace the metals. One can envision applying materials like these by means of ink-jet printing and solvent annealing, for example, eliminating masking and etching. It’s too soon to say whether the conductivity will be stable over long times.