Snowstorm - A Javascript Snow Effect
Snowstorm is a Javascript-driven snow effect that can be easily added to web pages. It is free for use, and easy to set up. A single Javascript file provides the functionality required. No images are used for the snow effect.
You can adjust the snow speed, the amount of snow, the “wind”, if and where it should stick (and if it should “melt”), and finally, whether the snow can react to the mouse moving (ie., “wind changes.”)
Snowstorm works under most of the old major browsers (IE 5.x+, Netscape 6+) as well as IE 6, 7, 8, Firefox, Safari and Opera, and the iPhone.
Snowstorm will eat up a lot of CPU, even on modern computers, because of the number of elements being moved around the screen at once.
Demo: http://www.schillmania.com/projects/snowstorm/
License: License Free