NOVELTY - The dissipater (2000) has a set of periodic hyperbolic surfaces i.e. paraboloid polyhedral inter connected shells, forming a continuous surface-structure, and enveloping contiguous tunnels through the surfaces. The shells are manifested in the structure. The tunnels are arranged according to a dual-intertwined cubic network pair. The shells include a thickness of 7 to 20 centimeter when the shells are made of reinforced concrete, and the shells include a thickness of 1-10 mm when the shells are made of metal or a composite material. The shells are covered with epoxy, and include ballast.    USE - Permeable, sponge-like wave-energy dissipater for use as a breakwater to protect land front mass from erosive power of sea. Can also be used as sound-absorber and acoustic barrier (all claimed) for indoor and outdoor use.    ADVANTAGE - The shells made of concrete are covered with an epoxy that coats the surfaces, thus increasing the lifespan of the breakwater. The dissipater absorbs the energy as the generated turbulence/friction by the waves burst into the interior of the dissipater, thus providing energy attenuation in an efficient manner. The ballast is converted into fill-material tanks when the dissipater is ground attached, thus increasing mass of the dissipater, improving stability of the breakwater, and reducing the need of anchoring-founding down to complete annulment.    DETAILED DESCRIPTION - The dissipater is constructed from material selected from a group consisting of concrete e.g. reinforced concrete, shotcrete, ferrocement, fiber-reinforced concrete, metal sheet, plastic resin and composite material, the structure is selected from a group consisting of cubic structure, diamond lattice structure, cube centered lattice structure, edge centered lattice structure and octet lattice structure, and the concrete includes reinforcing material selected from a group consisting of corrugated sheets of metal, plastic, composite material, ferrocement, fiber reinforced plastics, meshes made of metal, plastics, and composite material. INDEPENDENT CLAIMS are also included for the following:    (1) a mold for producing a concrete polyhyparic shell    (2) a method for using the dissipater in sea    (3) a method for manufacturing a sponge breakwater mega-block at a concrete fabrication maritime plant.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of cubic lattice of tunnels.    Permeable sponge-like wave-energy dissipater (2000)