The Loader module provides a block displaying a page loading progress indicator as percentage or progress bar. I'll just post important parts of it as reference here, but the loader module now has its project page so the code here might get outdated. It's here to show the basic principle only.
(function($){/**
* A page loading progress object. Initialized by passing a "loader" element in
* which the loading progress will be displayed by a
* <div><span>[dynamicPercentage]</span>%</div>
*
* e.g. Insert <div id="loader"></div> inside your page.tpl.php (or html...)
* then follow usage :)
*
* Usage:
* $('#loader').loader({options});
*
* Options:
* 'wrapper': $(document.body),
* The element in which we check for the images to load
Following Jan Sorgalla's example of a circular carousel, I had to do get this working with switching content associated with each carousel item. Since the circular carousel solution simply reloads items after each other, we have to keep track of what is where. In my case it was team members of a company website, and you want their name and info to keep up with their picture moving left and right.
Here's my take at a sliding thumbnail link with jquery.
Edit (02/04/09) : removed the first line in the first hover section with the .siblings() selector and set the queue parameter to false in the animations, otherwise the thumbnails could animate themselves for hours if you moved your mouse over them quickly ;)