Simple n-body solar systems

I often wish my skills in physics allowed me to understand gravity better. But, alas, I’m stuck with a rather sophomoric comprehension of the fundamental force. However, I can still play around with it. The image below shows the trajectories of a several thousand particles as they interact due to Newtonian Gravity, i.e. the inverse square law.

Watch several of the systems evolve in time:

I was so pleased with the outputs of this that I did invest in some printed versions (and a totebag and t-shirt). They are now on my office walls: