Flexo is a java-based game engine made to keep game development simple. It covers most of the topics needed in a videogame such as graphics, sound, user input, path finding and much more.
All the modules are built-in, so they automatically share the data in-between. For example, the physics engine will update the position of a graphic object and a sound emitter without coding anything.
It's been designed to be portable, easy to use and efficient. The goal of the engine is to handle all the repetitive technical work so that you can concentrate on what's important: the game.
I have to warn you that it isn't exactly a full 3D engine. It's built around the idea of rapid game development, so it is focused on 2D animated sprites and 3D static backgrounds. The physics module is also 2D based. On later versions maybe full 3D animated objects will be added.
What about GettingStarted? or maybe you prefer to watching it in action!
Videos: http://es.youtube.com/view_play_list?p=CEDA443E8D885D9F
Screenshots (a bit old): http://picasaweb.google.es/MiguelHerreroObeso/FLEXO
If you find a bug, need a new feature or just help, ask in the Flexo google group: http://groups.google.es/group/flexo-engine