Midgard2 is a content repository for desktop and web applications that provides common data access rules, signals about changes, and objects instead of SQL. It has a scriptable data model, synchronization and sharing capabilities. Midgard2 is part of the Midgard Project, a free software project since 1999 that aims to provide a content repository beyond just a CMS. It allows building web applications using its MVC framework and integrating with applications like Tomboy and Conboy.