Here you can find some experiments and tests with Concrete5 content management system, including add-on tests, templates etc.
Right now i'm testing Concrete5 - an CMS (content management system) that runs this site. So far so good. Though i should admit that Concrete5 isn't "lightweight solution". It's too massive (though powerful) for very simple sites. But I like it so far. Now i'm upgraded to version 5.3.3.1. Except i faced problems with non-latin characters. But i dont know whether it hosting issue or CMS problem. Othervise it works fine for me. With other versinos i had trouble with "fine links" - as on this server PHP runs in CGI mode.