The book presents the state of the art in high performance computing and simulation on modern supercomputer architectures. It covers trends in hardware and software development in general and specifically the future of vector-based systems and heterogeneous architectures. The application contributions cover among others computational fluid dynamics, physics, chemistry, astrophysics, and biology. Innovative application fields like multiphysics simulations and material science are presented. Furthermore, the use of supercomputers in the growing field of medical simulations is shown. All papers were chosen from presentations given at the second Teraflop Workbench Project Workshop held at the High Performance Computing Center Stuttgart (HLRS) in March 2005.