Zena, the most powerful Ruby on Rails CMS
Zena has been designed from the ground up to SCALE to huge amounts of data and provide all the tools to handle this growth.
You can watch the videos to get a first idea.
With zena you can create a web site and easily update it’s content without taking the phone to reach your webmaster. But unlike most other tools, there is no admin interface in zena. You add, remove and update the content where you and your users see it: on the page.