Textpattern

IMO, Textpattern is the best opensource content management system out there. It is flexible enough to be used in literally any application, but still maintains its lightweight feel. it's not too much to use it for a tiny 1 page blog, and at the same time, a multidimensional portal would run flawlessly in it.

Better than all the rest because:

It is very stable and lightweight; works 'out of the box' or simply paste and activate plugins to get extra features you fancy; installs in minutes; upgrades are few and only take minutes; fast learning curve; easy to use for non-technical people; easy for developers to customise it; excellent and friendly support forum supported by the core developers; free; no false promises; what you see is what you get is what you like.

All you need in a single package: extremely flexibile, lightweight, customizable, powerful.
At first sight can seem a bit not so user-friendly as other CMS but once you get to know it you may never try anything else.

We have implemented textpattern and foxycart to a fully-functional e-commerce application. The footprint is lightweight, updating is a snap, it is 100% portable, templating is designed with designers in mind(does not get in your way), and there is no messy store software. It Just Works(tm)!

very good content management system