There is the video, called "2 Hippy Girls Get Funky", in which Foucault's Pendulum experiments are reproduced. Notice that while the little ass swings faster than the big ass, they do indeed experience the same period:
http://www.myrefrigerator.com/videos/Trippy.WMV
Playing around, only to stumble upon a good 3D shooter background. I call this one Solstice Eve (Druids Must Die):