The Cloud bookshelf by Ronan & Erwan Bouroullec, with hollow compartments, is an extravagant furnishing element with a pop flair and an absolutely unforgettable design.   Made with rotational moulding technology, in white polyethylene, Cloud is a two-sided bookshelf that adds lightness to any ambiance, forming a configuration that can be personalised by the buyer: the modules can be interconnected as desired, using a retracting joint, to create a beehive structure.