How to Create a Particle System in Three.js
Some of the most fascinating Chrome Experiments to watch and experience are 3D Particles. The sdg Blog has a series of tutorials about programming 3D graphics in the browser using Three.js. Their sixth tutorial on the topic is how to create a particle system.

This Particle demo on chromeexperiments.com is gorgeous.
A particle system is a rendering technique that uses a large number of small sprites or other graphic objects to simulate “fuzzy” phenomena, like dust, explosions, fire, galaxies, or visual effects like magic spells. In the sdj Blog, they’ve chosen to provide a step-by-step tutorial on creating a particle system that simulates snow.

The result of the tutorial shows a blue cube rotating at the center while snow-like particles fall in a dark background.
The Three.js library really does make tackling the complexities of WebGL a bit less overwhelming. This tutorial is a great point to start learning a few of the basics of Three.js programming.
You can see the finished product here.