There are many image rotators available on the Web – I have built a couple myself. The interest of the one I propose is that it takes advantage of SharePoint’s built-in features to improve performance: instead of loading the full image, you can choose to use a thumbnail or a Web-optimized copy.
What I haven’t decided yet is how to add a description for each picture. Should it be displayed below the picture? Should it just show up on mouseover? Well, your ideas are welcome! Just keep in mind that it is a “Lite” version, so don’t expect fancy effects.