The Large Synoptic Survey Telescope (LSST) is a project to build an 8.4m telescope at Cerro Pachon, Chile and survey the entire sky every three days starting around 2014. The scientific goals of the project range from characterizing the population of largish asteroids which are in orbits that could hit the Earth to understanding the nature of the dark energy that is causing the Universe's expansion to accelerate. The application codes, which handle the images coming from the telescope and generate catalogs of astronomical sources, are being implemented in C++, exported to python using swig. The pipeline processing framework allows these python modules to be connected together to process data in a parallel environment.
The goal of the CGAL Open Source Project is to provide easy access to efficient and reliable geometric algorithms in the form of a C++ library. CGAL is used in various areas needing geometric computation, such as: computer graphics, scientific visualization, computer aided design and modeling, geographic information systems, molecular biology, medical imaging, robotics and motion planning, mesh generation, numerical methods... More on the projects using CGAL web page.