FreeCAD is an Open Source CAx RAD based on OpenCasCade, Qt and Python. It features some key concepts like macro recording, workbenches, ability to run as a server and dynamically loadable application extensions and it is designed to be platform independent.

Orc is a library and set of tools for compiling and executing very simple programs that operate on arrays of data. The "language" is a generic assembly language that represents many of the features available in SIMD architectures, including saturated addition and subtraction, and many arithmetic operations.

FATSort is a utility that sorts FAT16 and FAT32 partitions. It even can handle long file name entries. It reads the boot sector and sorts the directory structure recursively. This is for example useful for sorting the files on your MP3 player when it doesn't implement a sorting function itself.