libcdaudio is an unmaintained but portable library that provides wrapper functions to audio CD drives and CDDB and CDIndex database access. cdcd is a commandline CD player using libcdaudio's CDDB and CDIndex functions.
Simple and easy to use wrapper for GLSL (OpenGL's shading language). The functionality is similar to Nvidia's Cg. It is now very easy to use GLSL programs in your applications if you know how Nvidia's Cg works.