PyParticles
PyParticles is an opensource particles simulation tool box entirely wr
...It support the most popular integrations methods and the most relevant forces model. It also offer a nice looking OpneGL interface or at your preference a Matplotlib based GUI.
PyParticles as a forces models implements Gravity, spring, constant force and electrostatic and the user defined vector field force.
As a integrations method it includes Euler, Midpoint, Runge Kutta, Störmer Verlet and Leap frog.