Paul Irish, how does he do it?

How does Paul 开发者_StackOverflow社区Irish get that cool effect with the mouse on the sidebar?

He uses HTML5 CANVAS with http://mrdoob.com/120/Harmony in Ribbon Mode.

EDIT: He Forked the code and release his own version for MouseMove. you can download it here. https://github.com/paulirish/harmony

http://paulirish.com/harmony/harmony.js Here is how.

Yes its a HTML5 functionality.

Seems like this is the Javascript that does that effect: Harmony

Here's a link from the webpage.