BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
The bitap library is a clean implementation of regular expression (regex/grep) string matching using the bitap algorithm. Approximate (a.k.a. fuzzy) matching is allowed. This is the same algorithm as the one used in Glimpse and agrep, but it is much more complete with regard to regular expression syntax, and is much cleaner.
The National Space Science Data Center's (NSSDC) Common Data Format (CDF) is a self-describing data abstraction for the storage and manipulation of multidimensional data in a platform- and discipline-independent fashion. It consists of a scientific data management package (known as the "CDF Library") that allows programmers and application developers to manage and manipulate scalar, vector, and multi-dimensional data arrays.