GLAME (GNU/Linux Audio Mechanics) is meant to be the GIMP of audio processing. It is designed to be a powerful, fast, stable, and easily extensible sound editor for Linux and compatible systems. It has full support for non-destructive editing including undo/redo and applying LADSPA effects. Its supported platforms are Linux, BSD, IRIX, and OS X. It uses guile and libxml, and the GNOME libs available is highly recommended. MP3 and Ogg files can be processed if libmad and libvorbisfile are installed.
Sizzle is a Scheme interpreter for embedding into C applications and for standalone scripting. It implements a nearly complete subset of R5RS Scheme, adding a lot of primitives for U*ix scripting, regular expression searching, a simple module system, dynamic library linking, powerful string processing procedures, and much more. It includes a user's guide and an embedding manual in texinfo format, some examples, the embedding library, and a standalone interpreter for interactive use and scripting.
STklos is a free Scheme System conforming to R5RS. The implementation is based on an ad-hoc Virtual Machine. It can also be compiled as a library, so that one can easily embed it in an application. Its features include an efficient and powerful object system based on CLOS, a simple-to-use module system, implementation of the full tower of numbers defined in R5RS, and easy connection to the GTK+ toolkit. STklos is the successor of STk, a Scheme interpreter tightly connected to the Tk toolkit.