AA-lib is a low level gfx library just as many other libraries are. The main difference is that AA-lib does not require graphics device. In fact, there is no graphical output possible. AA-lib replaces those old-fashioned output methods with a powerful ASCII art renderer. The API is designed to be similar to other graphics libraries.
The ATLAS (Automatically Tuned Linear Algebra Software) project is an ongoing research effort focusing on applying empirical techniques in order to provide portable performance. It provides C and Fortran77 interfaces to a portably efficient BLAS implementation, as well as a few routines from LAPACK.
Allegro is a multi-platform game library for C/C++ developers that provides many functions for graphics, sounds, player input (keyboard, mouse, and joystick), and timers. It also provides fixed and floating point mathematical functions, 3D functions, file management functions, compressed datafile, and a GUI.
The mission of the Apache Portable Runtime (APR) project is to create and maintain software libraries that provide a predictable and consistent interface to underlying platform- specific implementations. The primary goal is to provide an API to which software developers may code and be assured of predictable if not identical behaviour regardless of the platform on which their software is built, relieving them of the need to code special-case conditions to work around or take advantage of platform-specific deficiencies or features.
Audiality is a highly scalable and portable audio engine and synthesizer. MIDI files are used in combination with scripting and modular synthesis, to minimize file sizes and maximize flexibility. Audiality can be used as a music and sound effects player in multimedia productions, or as a realtime MIDI synthesizer.
Autodl2 is a simple to manage and extensible file transfer system that can be configured simply using a configuration file. The system is designed to be lightweight and handle multiple file transfer protocols. Currently only SFTP is supported, though other systems can be added via a plugin system.
BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
BeOS 5 PE Max Edition is a distribution made using the free version of BeOS 5 (called Personal Edition) with a number of drivers, add-ons, and software. It includes the new development tools from the OpenBeOS team Web site, but you will also be able to select the old tools. It only contains freeware and shareware demos. All the code it contains is legal under the MIT, GPL, or LGPL licenses.