Wow, this is an impressive toolkit for manipulating the DOM. Make sure to check out the demos.
qooxdoo is an Open Source (licensed under LGPL) DOM-based javascript toolkit. qooxdoo continue where simple HTML is not enough anymore and this way it can you help to get your rich web application interface done easier than ever. qooxdoo includes simple to use focus and event interfaces. qooxdoo work in most of the current browsers. This also include recent versions of Opera and Safari. You don’t anymore need to detect the client browser if you work with qooxdoo widgets.