Did you ever need an easy way to create thumbnails, add a watermark, or do other types of image processing in Joomla? If so, you should check out Daniel Ghilea's JImageLib extension. For his GSoC 2009 project, he has created a library of built-in functions that make it incredibly easy to do all sorts of image processing inside your Joomla! extension or website. Great job, Daniel!
Webinar: Introducing JImageLib