SVG-Verlet.js is a rather nice looking SVG animation library from Mike Tucker. Most of the library’s functionality was extracted out of Mike’s portfolio and features include mouse pull, gravity, wind and noise warp. It’s written in CoffeeScript, but don’t panic, writing CoffeeScript isn’t required to use the library. That’s a nice touch.
If you’re into SVG and physics, this is definitely one for you to check out!