In the last decades, virtual reality technology has been increasingly used in many applications and it is possible to observe the advent of virtual reality solutions based on multi-projections in many research centers around the world. The goal of this document is to present the research and developments related to the construction of a completely immersive multi-projection system based on commodity computer clusters called CAVERNA Digital. An updated panorama of the state-of-art multi-projection virtual reality technologies is presented. The concept and taxonomy of commodity computer...