Metacosm is a framework for computer role playing games in Java. An example called ZHeroeZ is also provided. Some of the project's objectives are object oriented design, world persistency (all actions should have a long term impact on the world), coherent time management (time is the same for everybody in the same world), a graphical editor, and choice in client user interface. All creatures can be player or AI controlled by design.
The Metacosm project has been started by a bunch of former mud addicts (and classical RPG too), who would like to add a lot more background to their adventures than plain mob-bashing.