In recent years, a new branch of nanoscience/nanotechnology seems to be emerging. This branch is characterized by the application of preparation methods and/or the diagnostic tools developed in nanoscience/nanotechnology in order to perform either new, decisive experiments or to open the way to novel applications in areas of science that were originally not related to nanoscience/nanotechnology, such as cancer research or quantum physics. In order to highlight the diversity of this new branch, we shall discuss the following four areas in which methods of nanoscience/nanotechnology are applied to other areas of science: (1) cancer therapy, (2) cellular labeling, (3) the synthesis of solid materials with tunable atomic structures, and (4) the new opportunities provided by nanoscience/nanotechnology to probe the limits of quantum physics, one of the classical problems of physics.