Computational multiscale modeling encompasses a wide range of end-products and a great number oftechnological applications. This paper provides an overview of the computational multiscale modeling approach based on utilization of MBN Explorer and MBN Studio software packages, the universal and powerful tools for computational modeling in different areas of challenging research arising in connection with the development of novel and emerging technologies. Three illustrative case studies of multiscale modeling are reviewed in relation to: (i) the development of novel sources of monochromatic high-energy radiation based on the crystalline undulators, (ii) controlled fabrication of nanostructures using the focused electron-beam induced deposition, and (iii) ion-beam cancer therapy. These examples illustrate the key algorithms and unique methodologies implemented in the software.