Chitin – ‘the cellulose of the sea’ – is a structural polysaccharide that is a major constituent of the exo-/endo-skeleton of marine crustaceans and cephalopods, and is the 2nd most abundant biopolymer on earth only after cellulose. Ever since its discovery in the early 19th century, chitin has been considered a promising material due to its atypical yet compelling combination of mechanical and physicochemical properties, such as high elastic modulus (150 GPa), biodegradability, and excellent biocompatibility. Despite the promising traits, however, it is only quite recent that scientific interest on chitin has thrived and the utilization of chitin for engineering applications has revisited considerably. In this presentation, I will introduce some of my research endeavors to create structural/functional materials (e.g., transparent nanopaper) using chitin nanofibers (ChNF) as the basic building-blocks. I will also describe proof-of-concept examples of electronics and energy devices constructed using the ChNF paper platform.