We introduce a novel magneto-mechanical device to simulate viscoelastic substances in a rotational rheometer. The device can serve as a calibration standard to calibrate the measurement of the viscous and elastic properties of a substance or as a benchmark for measuring methods and device testing procedures. We present the mechanical and rheological backgrounds of this device, describe its design, and present the results from basic rheometric measurements, i.e., frequency sweeps, creep recovery, and cessation-of-shear experiments. We conclude with remarks on possibilities of extending the concept by modeling a broader spectrum of substances and the application in dynamic mechanical analyzers.