In this paper, we consider a thought problem intended to force consideration of fundamental limits for energy sources, sensors, computing elements, and communication systems as fundamental system dimensions are reduced to the few micron regime. Design of integrated systems at this level are shown to literally require the allocation of atoms for the various functions. We argue that although there are no fabrication technologies for systems on this scale and the tradeoffs between system functions are extreme, systems on this scale might be feasible; given end-of ITRS technologies.