ExtJS is a popular Script Library that combines the existing Libraries Yahoo!, jQuery and Prototype + Scriptaculous. The result: you have a only way to create GUI components in your Web applications.
If you want to have a quick look, visit the API and see the examples.
WordPress
Google + 
Facebook
In Codestore you can find how ExtJS can be addapted to a nsf database: Ext.ND JavaScript Library (Link)