The design and development of novel functional nanomaterials has drawn intense interest because of their potential applications in electronics, physics, chemistry, biology, and medicine. An effective design strategy requires a thorough understanding of various interaction forces and mechanisms which prevail in such small dimensions. The wide manifestation of π systems in broad classes of nanomaterials ranging from organic polymers to fullerenes implies that a fundamental understanding of these intermolecular interactions from both theoretical and experimental perspectives would be of value. The present work initially details our efforts to theoretically investigate the characteristics of the interaction of these π systems (olefinic, aromatic, and fullerenes) with a wide range of countermolecules ranging from single atoms to rare gases to elemental hydrides to cations to Lewis acids. The information obtained from these theoretical investigations was then employed in the design of aesthetically appealing and functionally useful ionophores and organic nanotubes, The synthesis and characterization of the latter revealed the presence of infinitely long one-dimensional H-bond arrays. The relevance of these one-dimensional H-bond arrays in both material science and biology and the utility of this design strategy in developing functional nanosystems would also be discussed.