PROS: Easy/Fast setup, Creates automatic perfect search engine friendly URLs

CONS: Fairly expensive for multiple installations unless you opt for the server wide license

Sakic's SEF Advance

We all know that Joomla is not the most SEF (Search Engine Friendly) software on the planet out of the box; but fret not, Sakic's SEF Advance to the rescue.

Sef Adv. (as it's commonly known) will turn those pesky unfriendly and quite frankly ugly links and turn them into keyword rich, nice looking and human readable URLs which will help your search engine ranking dramatically.

SEF Advance  will automatically convert all URLs of your Joomla site to new, advanced URLs as you install it. It will also redirect all requests to old-style SEF and non-SEF URLs to corresponding advanced ones at the same time that it prevents Joomla from creating different URLs with duplicate content which could hurt your ranking in the search engines. 

SEF Advance comes in two flavors - SEF Advance for Joomla 1.0x and SEF Advance 2008 which is 1.5x compatible.

Installation

Installation could not be quicker and easier; all you need to do is install the component via the admin installation function and upload a new updated .htaccess file into your root directory (The SEF ADV. 2008 version does not even require you to do that).