MIT/GNU Scheme is an implementation of the Scheme programming language, providing an interpreter, compiler, source-code debugger, integrated Emacs-like editor, and a large runtime library. MIT/GNU Scheme is best suited to programming large applications with a rapid development cycle. Recent versions of the system are supported on the following platforms: GNU/Linux, *BSD, OS/2, and Windows.
GNU TeXmacs is a free wysiwyw (what you see is what you want) editing platform with special features for scientists. The software aims to provide a unified and user friendly framework for editing structured documents with different types of content: text, mathematics, graphics, interactive content. TeXmacs can also be used as an interface to many external systems for computer algebra, numerical analysis, and statistics. New presentation styles can be written by the user and new features can be added to the editor using Scheme.
ics.el is a comint based Emacs major mode for handling the text portion of communications with internet chess servers such as FICS and ICC. It is written in Emacs-Lisp and works best in conjunction with a graphical interface such as Xboard. It handles colour highlighting and "buttonisation" (making certain portions of text active so that, for example, you can challenge opponents with a single mouse click) as well as command recall and editing and automation of commands based on regexps seen in the ICS output, all highly customisable using Emacs lisp.
The Remembrance Agent (RA) watches your over your shoulder and continuously updates a list of documents relevant to what is being typed or read in an Emacs buffer. Suggestions are then displayed in their own window at the bottom of the frame, and are continually updated every few seconds. The RA uses a multi-field information-retrieval back-end called Savant that can index several different kinds of files, including email archives, HTML, LaTeX, and plain text format.
Java Development Environment for Emacs (JDEE) is an Emacs-based integrated development environment (IDE) for developing Java applications and applets. Features include multiple code browsers, a JPDA-based debugger, method and field completion, template-based and procedure-based code generation, Java source code interpreter, context-sensitive help, and more.
XEmacs (formerly known as Lucid Emacs) is a powerful, extensible text editor with full GUI support, initially based on an early version of GNU Emacs 19 from the Free Software Foundation and since kept up to ate with recent versions of that product. XEmacs stems from a collaboration of Lucid, Inc. with Sun Microsystems, Inc. and the University of Illinois with additional support having been provided by Amdahl Corporation, INS Engineering Corporation, and a huge amount of volunteer effort.