emNewton2 is an implementation of Sir Isaac Newton's Law of universal Gravity, which roughly goes like this:
"Each particle attracts each other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them."
This plugin for Softimage's ICE can be used to create simulations that are driven by gravity, such as solar systems or stars with an accretion disc. Furthermore this plugin has a "fusion" functionality meaning that intersecting particles melt together.
emNewton2 is well integrated into ICE and works nicely with the built-in compounds such as forces, obstacles, subframe sampling and other effects.