Prototype : Easy Ajax and DOM manipulation for dynamic web applications
DOMAssistant : The modular lightweight JavaScript library, with CSS selectors, event handling, AJAX and complete Unicode support
Javascript Sound Kit : The Javascript Sound Kit is a wrapper around the ActionScript Sound Object, it makes it possible to use the Sound Object in Javascript the same way yo...
Wave.js : Audio visualizer library for javascript. Create dynamic animations that react to an audio file or audio stream.
jsmad : jsmad is a pure javascript MP3 decoder, based on libmad, with an ID3 decoder written from scratch.
TogetherJS is a free, open source JavaScript library by Mozilla that adds collaboration features and tools to your website. By adding TogetherJS to your site, your users can help each other out on a website in real time!