The Ejs Strange Harmonic Oscillator model displays the motion of two masses connected by a massless rigid rod and the masses may move without friction along two perpendicular rails in a horizontal table.  The energy of the oscillator system can be changed via a slider.  You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item.  

Ejs Strange Harmonic Oscillator model was created using the Easy Java Simulations (Ejs) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_ehu_oscillations_strange.jar file will run the program if Java is installed.  Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models.  Additional Ejs models for classical mechanics are available.  They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Please note that this resource requires at least version 1.5 of Java (JRE).