Nature is a great source of inspiration for creating structures that efficiently utilize materials and energy. An excellent example is trabecular bone, which is not only lightweight but also capable of supporting mechanical loads effectively during our daily activities. In this talk, I will present computational approaches to design bone-like porous structures for engineering purposes. The basic principle involves selectively placing material where it is necessary and eliminating material where it is less crucial. The formulation of porous structures is driven by a novel geometric criterion that regularizes the material distribution. Additionally, I will discuss numerical and geometric methods to reduce the involved computation. I will also establish connections between this computational design approach and advances in additive manufacturing (also known as 3D printing), which enable the physical realization of optimized porous structures. Throughout the talk, I will showcase various applications that benefit from this approach, including customized orthopedic implants and lightweight components for future mobility solutions.