PUBLIC MARKS from parmentierf with tags javascript & "open source"

MooTools is a compact, modular, Object-Oriented javascript framework designed to make writing extensible and compatible code easier and faster. MooTools lets you get the job done efficiently and effectively.

The Yahoo! User Interface Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications using techniques such as DOM scripting, HTML and AJAX. The UI Library Utilities facilitate the implementation of rich client-side features by enhancing and normalizing the developer's interface to important elements of the browser infrastructure (such as events, in-page HTTP requests and the DOM). The Yahoo UI Library Controls produce visual, interactive user interface elements on the page with just a few lines of code and an included CSS file. All the components in the Yahoo! User Interface Library have been released as open source under a BSD license and are free for all uses.

JavaScript for Rich Internet Applications. An open-source JavaScript library for creating rich internet applications. Rico provides full Ajax support, drag and drop management and a cinematics effects library.

JWChat is a full featured, web-based Jabber™ client. Written using AJAX technology it relies on JavaScript and HTML at the client-side only. It supports basic jabber instant messaging, roster management and groupchats based on the MUC protocol.