The 3-4-5 three-body problem. Place masses in the ratio 3:4:5 at the vertices of a 3-4-5 triangle. Drop. What happens? This problem, also called the `Pythagorean' or `Burrau' three-body problem has a long history.
3-4-5 three-body problem (the movie)
as a dance performance and: a post on the performance

Other sites I enjoy: ``burtleburtle '' Bob Jenkins site. eclectic; lots of interesting periodic orbits ....
Vanbderbei
Suvakov & Dmitrasinovi an older site- zero angular mom. equal mass 3 bdy; beginnings of a free homotopy coding ;
Sverre Aarseth, a champ of N-body integrators