Recent developments in nanotechnology have highlighted the innovative use of RNA molecules in techniques such as replication, molding, and embossing, enhancing the diversity and resolution achievable in nanomaterial fabrication. The inherent adaptability of RNA allows for the creation of complex, programmable nanostructures through 3D fabrication, reversible self-assembly, and self-repair capabilities, transforming its application in integrated biological nanofabrication. With a potential library of 100-nucleotide RNA sequences yielding up to 1.6 × 1060 distinct structures, RNA surpasses the complexity and diversity of many existing nanoscale systems. These advancements have also propelled RNA nanoparticles into emerging applications such as pathogen detection, where their ability to specifically recognize viral or bacterial sequences is critical; drug and gene delivery, leveraging their structural versatility for targeted therapeutic delivery; and direct therapeutic applications, particularly in cancer therapy to selectively target and modulate malignant cells. This chapter builds on previous discussions of RNA structure and function, integrating recent breakthroughs that establish RNA nanoparticles as a cornerstone of future nanotechnological and medical solutions.