Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.

Medium - Welcome to Medium, a place to read, write, and interact with the stories that matter most to you.

Textpattern - Textpattern is an elegant content management system that is free, open source software.

Ghost - Ghost is a fully open source, adaptable platform for building and running a modern online publication. We power blogs, magazines and journalists from Zappos to Sky News.

TYPO3 - TYPO3.com - Infos, SLAs, Extended Support Versions and more

Tumblr - A feature rich and free blog hosting platform offering professional and fully customizable templates, bookmarklets, photos, mobile apps, and social network integration.