NOVELTY - A thermal management assembly comprises a heat sink including a graphite layer having a first surface, a second surface, and a thickness comprising a graphene layer, where graphite layer is obtained by cleaving a graphene layer from a graphite sheet, where graphite layer exhibits a thermal conductivity, which is anisotropic in nature and is greater than 500 W/mdegreesC in a plane(s); and a support layer comprising a metal, a polymeric resin, and/or a ceramic disposed on a surface(s) of the graphite layer.    USE - For dissipating thermal energy from a heat-generating device e.g. fuel cells, nuclear reactor, automotive, electronic device e.g. microprocessor, lap top computers, and laser diodes, evaporators, and defense-related and spacecraft applications including spacecrafts and jet fighters.    ADVANTAGE - The heat sink with its ultra-thin fins offers optimized conductive thermal resistance with its combination of maximum thermal conductivity and minimum thickness; and offers optimized thermal management in terms of maximum amount of heat that can be removed in terms of weight of the heat sink (i.e. the fins), or the total surface area available for heat removal/cooling.    DETAILED DESCRIPTION - A thermal management assembly comprises a base thermally coupled to the heat generating device; and a heat sink thermally coupled to the base. The heat sink comprises a graphite layer having a first surface, a second surface, and a thickness comprising a graphene layer, where graphite layer is obtained by cleaving a graphene layer from a graphite sheet, where graphite layer exhibits a thermal conductivity, which is anisotropic in nature and is greater than 500 W/mdegreesC in a plane(s); and a support layer, which comprises a metal, a polymeric resin, and/or a ceramic, the support layer is disposed on a surface(s) of the graphite layer by a process consisting coating, brushing, spraying, spreading, dipping, laminating, or powder coating. Before the support layer is disposed on the graphite layer, the graphite layer is treated by plasma etching, ion etching, and/or chemical etching. The support layer comprises parylene, and formed by applying parylene onto a surface of the graphite layer, where parylene is applied onto the surface by brushing, dipping, spraying, or a chemical vapor deposition process. It comprises a metal foil backed by a thermally conductive adhesive layer. INDEPENDENT CLAIMS are also included for:    (1) a heat dissipating fin (14) for use in thermal management assemblies, the fin comprising a graphite layer;    (2) a cooling system; and    (3) a method for constructing a thermal management system.    DESCRIPTION OF DRAWING(S) - The figure is a perspective view showing an ultrathin/ultra-light heat sink with a honeycomb-like, cellular structure.    Base plate (12)    Heat dissipating fin (14)