A memory device includes a mechanical element that exhibits distinct bistable states under amplitude modulation. The states are dynamically bistable or multi-stable with the application of a drive signal of a given frequency. The natural resonance of the element in conjunction with a hysteretic effect produces distinct states over a specific frequency range. Devices with multiple elements that respond to different frequency ranges provided on a common contact are formed with improved density. The devices may be excited and read with magnetomotive, capacitive, piezoelectric and/or optical methods. The devices may be planar oriented or out of plane oriented to permit three dimensional memory structures. DC biases may be used to shift frequency responses to permit an alternate method for differentiating states of the element.