Lion is an emerging open source PHP framework for creating rich web applications as a combination of the most valuable features and patterns taken from the development community.
Maybe the most valuable feature within the framework, as a combination of a MVC and a MVP. The MVP allows to declare rich UI components within your templates, easing the integration with your own event handlers. Lion's component model handles AJAX communication in both ways: Direct and Reverse-AJAX.
From the architecture point of view, Lion is organized by context containers representing applications, being one of the most valuable benefits his IoC capability, a spring-style based dependency injection which let the framework work out the complexities of service instantiation, initialization and sequencing.