I have definitely read about a project where they made a physical model to represent/show the complexity of a software system to their clients. IIRC the project

I have definitely read about a project where they made a physical model to represent/show the complexity of a software system to their clients. IIRC the project involved doing a re-write of an existing system. Unfortunately, I can't remember exactly where I read this. Perhaps someone else here knows the details? Sorry I can't be more specific.