jQuery lightBox plugin is simple, elegant, unobtrusive, no need extra markup and is used to overlay images on the current page through the power and flexibility of jQuery´s selector.

The Rotator as I have come to call it will simply auto rotate through a list of images with a smooth fade effect without the need to include an extra plug-in on top of Jquery.

jQuery.spritely is a jQuery plugin created by Artlogic for creating dynamic character and background animation in pure HTML and JavaScript. It's a simple, light-weight plugin with a few simple methods for creating animated sprites such as the birds you see on this page, and dynamic scrolling backgrounds.

YoxView is a free Lightbox-type media and image viewer jQuery plugin. It's easy to use and feature-rich.

Picbox is a lightweight (around 5KB) javascript image viewer based on the excellent Slimbox by Christophe Beyls, and available using either the Mootools or jQuery frameworks. It features automatic resizing and zooming of large images, allowing them to fit in the browser or be viewed at full size.