This is meant to simulate how a solar system is formed. The masses are moved only by the gravitational force and plastic collisions between them.
The number you must enter represents the number of initial objects, their maximum random velocity, gravitational strength, size, screen size(for projectors). Play with those numbers until you see a nice result. I got a sun and 2 or 3 planets orbiting around it.
You can zoom in and out with the mouse wheel and move around by click-drag-release.