Beautiful toy for seeing planetary orbits

http://www.gunn.co.nz/astrotour/ has a beautiful toy for visualizing the orbits of the planets.

Make sure to watch the tour that demonstrates retrograde orbits. I've understood that for a long time. But I've never seen a better demonstration/explanation.

From the retrograde demo/tour I turned on long trails for each planet as observed from Earth.  And then I put Earth in the center of the observation.  And then I turned down the speed to 1 frame = 1 day.  Years snap by pretty quickly on my computer, but not too fast.  It's a beautiful spirograph, with each planet dipping towards earth on a regular pattern.

 No wonder early astronomers had such a hard time figuring out what was going on.  Until you make the conceptual leap of putting the Sun in the center of the universe the other planetary orbits make such a beautiful and consistent pattern.  Seeing that I would have been tempted to search for an explanation that left Earth in the center.