Librep is a shared library implementing a Lisp dialect that is lightweight, reasonably fast, and highly extensible. It contains an interpreter, byte-code compiler, and virtual machine. Applications may use the interpreter as an extension language, or it may be used for standalone scripts. Rep was originally inspired by Emacs Lisp. However one of the main deficiencies of elisp--the reliance on dynamic scope--has been removed. Also, rep only has a single namespace for symbols.
MDK (MIX Development Kit) provides tools for developing and executing, in a MIX virtual machine, MIXAL programs. The MIX is Donald Knuth's mythical computer, described in the first volume of The Art of Computer Programming, which is programmed using MIXAL, the MIX assembly language. MDK includes a MIXAL assembler (mixasm), a MIX virtual machine (mixvm) with a command line interface, a Guile-based virtual machine (mixguile), a GTK+ based GUI (gmixvm), and a mixvm-Emacs interface (mixvm.el). MDK utilities are extensible using Scheme.
XSLT-process is a minor mode for (X)Emacs that allows you to run a Java XSLT processor on a buffer and display the result in another buffer, or in a browser. You can also run the XSLT processor in debugging mode, setup breakpoints, run step by step, view local and global XSLT variables, and many more.
The bintrans Dynamic Binary Translator is a dynamic binary translator which runs programs on architectures they were not compiled for. It does this by dynamically translating the machine code of the programs to be run to machine code for the native architecture. It currently translates from i386 to PowerPC and from PowerPC to Alpha.
Charlemagne is a versatile genetic programming application. It includes a commandline client and an interactive console mode. It is written in Python and Lisp, and is user extensible to some degree in both languages. It features built-in input-output mapping support and provides the ability to define complex fitness calculations in Lisp or Python.
Nyquist is an elegant and powerful language for sound synthesis and music composition. Unlike score languages that tend to deal only with events, or signal processing languages that tend to deal only with signals and synthesis, it handles both in a single integrated system. It is also flexible and easy to use because it is based on an interactive Lisp interpreter. You can design instruments by combining functions (much as you would using the orchestra languages of Music V, cmusic, or Csound). You can call upon these instruments and generate a sound just by typing a simple expression. You can combine simple expressions into complex ones to create a whole composition. It runs under any Unix environment, MacOS, Windows 95, and Windows NT, and it produces sound files as output (or direct audio output under Windows).