TYPO3 is a enterprise-class solution that can handle large and complex websites. It offers the full gambit of advanced features like multilingual sites, and working with almost any database out there. It also has a broad base of extensions and developers that can add to its functionality.
Current Version: 4.4
Source: Open Source
Hosting: Your Server
License: GNU GPL
Database: MySQL, MS-SQL, PostgreSQL
TYPO3 is a modular system that can solve a variety of website needs. It’s really nice the way you are able to create pages with a variety of kinds of “content elements” like regular text, forms, filelinks, multimedia, etc. and then tell it where to go on your site. The system is highly configurable and could work for a variety of applications, especially bigger, more complex websites.
Even its fans admit that it has a steep learning curve when it comes to working with it. The system seems a little dated and could use some new attention. It doesn’t seem to be in very active development these days, considering the last update was released in March 2007.