SPIP is a Content Management System, for magazine / newspaper online publishing. It's used in newspapers as the "Le Monde Diplomatique", "Vacarme" and "ecrans.fr".
SPIP is free software, licensed under the General Public License (GPL).
The strength of this CMS is the way you can make new templates. Almost everything can be configured in the template design. It's an easy system for writter's and powerful for designers.
It allows internal discussions before the articles are published and external discussions after it's published.
Actual stable version: 2.0.3 (Jan 2008)
This CMS works in Dreamhost.