Particle Playground is a toolset which enables you to be creative in new ways of altering and rendering particles in your 3d application.
Particle Playground can process and create particles from images, meshes (static, moving, skinned/animated, procedural), painted and projected positions.
Manipulators can interact and alter the particles behavior over their lifetime, adding different types of forces and change of their properties.
All features can be called through scripting. It is also fully accessible through the Unity Editor's Inspector, where you can work with the settings through sliders and many times directly into the scene view with interactive tools. Do note that the framework is written in UnityScript (C# version will be distributed along with the package in the future).
You're highly encouraged to share your own creations on the Unity Asset Store - using the Preset Wizard to prepare your content for publishing.