Mapping/texturing inside of a box I'm trying to replace the content of a box in a video, I have used the tracking system to match the movement of the video box with the interior of the one rendered in Blender, but I am running trough what seems a simple thing but I can't manage to get done. 

I want the outside faces of the box to be invisible while hiding the inside of the box where the front wall of the box hides it, and the inside of the box to be rendered where visible. To do that I thought it would be as simple as making the face normals point to the inside of the box and giving a color only to the faces where normals are pointing to. But I can't manage to get that, am I going the wrong road? How can I achieve my goal?
CYCLES RENDER

To give a texture only to the inside of the box you may use a Backfacing output of the Geometry node.


Unwrap your mesh and set the nodes as pictured below. Use a Backfacing output as a factor for two materials/textures.




BLENDER RENDER

In Blender Internal you may also use the material nodes to achieve this effect.


Unwrap your mesh and give it a new material. Check the Use Shader Nodes box.


Now add two other materials- one for the inside and one for the outside of the box.


In the Node Editor window set up the nodes as pictured below.


You may also add just one material and create two others within it using nodes. Unwrap your mesh and add a new material. Check the Use Shader Nodes box.


Set up the material nodes as pictured below.