In the recent years, we are increasingly endowing devices and machines with the abilities to "sense", "understand", and "interact" with us and the physical world, aided by the rapid advances in natural sensing and perceptual computing technologies. In this article, we describe a new class of intelligent systems and immersive applications based on real-time 3D sensing, including interactive computing devices, autonomous robots and drones, as well as augmented and virtual reality systems, blurring the border between the real and the virtual words.