Understanding the nature of turbulent flows remains one of the outstanding questions in classical physics. Significant progress has been recently made using computer simulation as an aid to our understanding of the rich physics of turbulence. Here, we present both the computer science and the scientific features of a unique terascale simulation of a weakly compressible turbulent flow that includes tracer particles. (Terascale refers to performance and dataset storage use in excess of a teraflop and terabyte, respectively.) The simulation was performed on the Lawrence Livermore National Laboratory IBM Blue Gene/ L™ system, using version 3 of the FLASH application framework. FLASH3 is a modular, publicly available code designed primarily for astrophysical simulations, which scales well to massively parallel environments. We discuss issues related to the analysis and visualization of such a massive simulation and present initial scientific results. We also discuss challenges related to making the database available for public release. We suggest that widespread adoption of an open datasel model of high-performance computing is likely to result in significant advantages for the scientific computing community, in much the same way that the widespread adoption of open-source software has produced similar gains over the last 10 years.