Chyrp is a blogging engine designed to be very lightweight while retaining functionality. It has powerful theme and extension engines, so you can personalize it however you want. The code is well-documented, and it has a very strong structure that's loosely based on the MVC design pattern. Chyrp allows importation from several different blogging engines and uses a system called "feathers", which are basically templates for custom posts.
RedKite CMS is a Content Management System built on top of Symfony2 and Twitter-Bootstrap frameworks. It lets you manage the content of your website inline, using an interface designed to increase the quality of the user experience. You are not required to have technical skills related to Web programming to build a website using this CMS.