The Kawa Scheme System is a full Scheme implementation, completely written in Java. Scheme functions and files are automatically compiled into Java byte-codes. Kawa does some optimizations, and the compiled code runs at a reasonable speed. It provides the usual read-eval-print loop, as well as batch modes. The Kawa compilation framework is also useful for implementing other languages on top of JVM. There is active development of XQuery (the XML query language), and less active development of Emacs Lisp, Common Lisp, and EcmaScript.
ecasound.el is an interface to ecasound from within Emacs. It allows you to use an inferior ecasound process in an comint-derived mode. It features context-sensitive completion and wizards for adding chainoperators and the like. It allows you to write ECI-based applications in Elisp.
ECB is a source code browser for (x)emacs. It displays a couple of windows that can be used to browse directories, files, and file contents like methods and variables. It supports source code parsing for languages like Java, C, C++, Elisp, Scheme, Perl, TeX, LaTeX, etc. In addition, it offers an (optional) permanent "compile window" at the bottom of the emacs frame, which is used to display all help and compile output. The rest of the frame is called the "edit area", which can be divided into several edit windows that are used for editing the sources. Deleting some of the edit windows neither destroys the compile window nor the browsing windows. It requires the CEDET suite.
Versatile Cursors for GNUemacs is a set of emacs commands managing an "item" cursor (e.g. a word, expression, sentence, or defun). It quickly re-assigns the cursor keys between these as needed. Built on this are high-level actions such as converting code blocks to separate functions. This provides elegant and concise editing, and is pedal- and voice-friendly.