Sophisticated, lightweight & simple CMS, homepage: Bolt.cm

Bolt is a tool for Content Management, which strives to be as simple and straightforward as possible. It is quick to set up, easy to configure, uses elegant templates, and above all: It's a joy to use. Bolt is created using modern open source libraries, and is best suited to build sites in HTML5 with modern markup.

From a technical perspective: Bolt is written in PHP, and uses either SQLite, MySQL or PostgreSQL as a database. It's built upon the Silex framework together with a number of Symfony components and other libraries. Bolt is released under the open source MIT-license.

Create a new folder, and clone from github. Then use composer to get the Silex micro-framework and components:

git clone git://github.com/bobdenotter/bolt.git bolt
cd bolt 
curl -s http://getcomposer.org/installer | php
php composer.phar install

And you're good to go.

More detailed instructions can be found in the Setup section in the documentation.