On PHPBuilder.com today Voja Janjic has written up a "top ten" list of the most useful Joomla components you can use for your Joomla-based site.
Joomla, the PHP-based, open-source content management system (CMS), has grown in popularity thanks to its wealth of templates, modules and components, as well as its ease of installation. In this article I present the most useful Joomla components I have found in my Web development. They cover everything from e-commerce to internationalization to SEO
Components that made the list include:
Each item has a brief description of what it does and a link of where to find the latest version.