FullCalendar is a jQuery plugin that provides a full-sized, drag & drop calendar like the one below. 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). The documentation for FullCalendar is available on their website, http://arshaw.com/fullcalendar/.