This a game engine I've been working on for a while, and might again at some point. Here are some key features:

• Entity-Component-Model.
• Extremely modular, maybe a little too modular.
• Uses XNA for asset management and rendering.
• 2D top-down space shooter as testing game.
• Data driven, editor for prefabs (entities) with preview.
• Contains port of Box2D that can be used in multiple threads at once.
• Contains a few

To build this you'll need IronPython (2.7.x) and NLog (2.x) installed on your system. For some modules you may have to adjust library references (libs are located in the Libraries directory).