This invention generally relates to a set of parallelepipedal bodies (cells) capable of matingly compatible engagement for interconnection, so as to allow up to three degrees of freedom in the sliding movement of an individual cell or grouping of cells about a grouping of other interconnected cells from the set. Each cell may be monolithic or constructed from six face plates. For cubic and rhombohedral forms, the face plates are designed to interlock in construction with any other face plate to form a cell, regardless of the orientation of the face plates. A first set of cells utilizes a uniform face plate, each cell differing only in the orientation of this uniform face plate about the other uniform face plates on the cell. A second set of cells utilizes two different but matingly compatible face plates. Again, each cell differs only in the orientation of either of the matingly compatible face plates about the other face plates on the cell.