I’ve used Joomla for about 4 years now. In these 4 years I came accros a lot of extentions for Joomla. There are a lot of extentions availaible. You name your functionality and there wil probably be an extention for it. This article is an overview of the best free extentions I used. You can find them by going to http://extensions.joomla.org/, navigating to the proper section or search for the name of the extention.

• Virtuemart; E-commerse shop
• Multithumb; Images as thumbs in content
• BriasKiss; Slideshow module non-Flash
• aiContactSafe; Customizable contact form
• ccBoard; Bulletin Board, Forum
• JoomFish; Multi-lingual site
• Sh404SEF; Search Engine optimization, Search Engine friendly URL’s
• JoomlaPack; backup your complete website

Don’t forget to test the extention first in your test environment (I am sure you have one, if not create a directory “test” on your webserver and install Joomla here also, voilla; a test environment). Before installing the extention in production make sure to backup your site.