This is a framework for prototyping games that I made for kicks.
I recommend going with Unity3D for a full engine.
If you're familiar with Unity3D, you'll have an easier time understanding what's going on here. The important point is that all the action happens in components. Entities are merely the strings that tie together a set of components.
Both entities and components have activate() and disable(), but only components have update(). So if you want to do special game logic on every tick, then you need to make a new component, and probably give it a Signal or two that the entity listens for.
Communication between an entity and a component, and between components, is done through Signals, or simple properties. The most powerful aspect is components sharing references through entities. For example, most entities have a position (Vec2), so to ensure both the view and physics components stay in sync, they both simply reference their parent entity's position property--no work is needed from the entity itself.