1. A method of inducing a programmable resistance in a chalcogenide device exhibiting negative differential resistance wherein the chalcogenide device is an analog variable resistor, the method comprising: configuring the analog variable resistor to change resistance states in response to electrical pulses, where the pulses fall within at least four possible voltage potential ranges corresponding to at least (1) a small decrease in resistance, (2) a small increase in resistance, (3) a large decrease in resistance, and (4) a large increase in resistance, wherein possible voltage potential ranges (2) and (4) are related such that at least approximately five electrical pulses in possible voltage potential range (2) cause a resistance change equivalent to approximately one pulse in possible voltage potential range (4), and further wherein possible voltage potential ranges (1) and (3) are related such that at least approximately five electrical pulses in possible voltage potential range (1) cause a resistance change equivalent to approximately one pulse in possible voltage potential range (3); and applying an electrical pulse to the chalcogenide device, wherein the electrical pulse falls within one of the at least four possible voltage potential ranges.