Shader Node: Lighting, PBR?

Hi there.
I would like to use the shader nodes to add behavior to the common Lighting or the PBRLighting material. The thing is that I cannot find any shader node that does the same thing as the said Lighting materials. Blame me if I’m wrong, but I think that i’ve seen some Lighting nodes here on the forum. Do they really exist?

There are no stock shader nodes that replicate the lighting or PBR shaders behavior.
I still have to make them, or maybe some savvy monkey will contribute them.