Ajax

Chained is simple plugin for chained selects. It works with both jQuery and Zepto. You can choose from two different versions. Use class based version if you do not want to make external queries. It uses HTML class names of select options to decide content. To create selects from AJAX queries use remote version instead. This version makes an external AJAX query and uses the returned JSON to build child selects.  

Flexigrid, a rich data grid jQuery plugin, has the ability to connect to XML and JSON data by using Ajax to load the content.   Flexigrid - Features: Resizable columns Resizable height and width Sortable column headers Cool theme Can convert an ordinary table Ability to connect to an ajax data source (XML and JSON) Paging Show/hide columns Toolbar (new) Search (new) Accessible API Resizable Width JSON Support Toolbar Table Toggle Button Show/Hide Columns control have been move

jQuery Cascading Dropdown is a simple and lighweight jQuery plugin for creating cascading dropdowns. You can set the default selected dropdown item in a dynamic dropdown scenario and combine both static and dynamic dropdowns.  

FullCalendar is a jQuery plugin that provides a full-sized, drag & drop calendar. It uses AJAX to fetch events on-the-fly for each month and is easily configured to use your own feed format (an extension is provided for Google Calendar). It is visually customizable and exposes hooks for user-triggered events (like clicking or dragging an event).