TYPO3 is a free and open source enterprise level content management system. It is written in PHP. It has become a wide spread content management systems (CMS) on the web and in intranets. It is more popular in Europe, probably, because is created initially... 
Why this project?
Some times ago I search the Internet for somebody who can add some spicy stuff to my web projects. And It took me a lot of time and o lot of nervs. And here come the ideea!
Who have enough time to serch the web where exist more than 30 milions of blogs and more than 100.000 are created each day.
Owner