Complex photonic systems, in particular, semiconductor lasers with delayed coupling, are of great relevance in many applications, especially in the field of telecommunications. However, to achieve its functionality, an understanding of the fundamental dynamical properties, the technical realization and a final analysis and synthesis of the system is needed. In this talk, we present a complex photonic system made practical for a concrete application: the generation of random bits. We implement an ultra-fast random bit generator based on the complex dynamics of a semiconductor laser. We show that dynamics, acquisition and post processing conditions play key roles for the randomness of the bits. With the proper balance between these three factors, we demonstrate the potential of the system to generate random bits at rates up to 160 Gbit/s for 8-bit digitization and up to 480 Gbit/s for 16-bit digitization. Finally, we discuss our results in the context of information theoretic limitations.