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.
CMUCL is a free, high performance implementation of the Common Lisp programming language which runs on most major Unix platforms. It mainly conforms to the ANSI Common Lisp standard. CMUCL provides a sophisticated native code compiler; a powerful foreign function interface; an implementation of CLOS; the Common Lisp Object System; which includes multimethods and a metaobject protocol; a source-level debugger and code profiler; and an Emacs-like editor implemented in Common Lisp. CMUCL is maintained by a team of volunteers collaborating over the Internet, and is mostly in the public domain.
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.
crypt++.el is a package of Lisp functions that recognize automatically encrypted and encoded (i.e., compressed) files when they are first visited or written. The BUFFER corresponding to the file is decoded and/or decrypted before it is presented to the user. The file itself is unchanged on the disk. When the buffer is subsequently saved to disk, a hook function re-encodes the buffer before the actual disk write takes place.
Eev.el is a simple Emacs Lisp library that lets you treat portions of a text file as shell commands, chunks of code for programming languages or as hyperlinks; its intention is to let people record into plain ASCII files their interaction with the computer, and to let them edit and play back any block of code in those files easily. The hyperlinks can point to places in manpages, Info pages and text or HTML files, and they are seen as comments by all programming languages; using them you can place pointers to all relevant online sources of information inside the code.
Gnutran is a simple, Emacs-based front-end to a number of machine translation engines available on the Web. It can send emacs buffers to a translation engine, request a translation (e.g. English to Portuguese) and display the result on a new window. GNUTRAN interoperates with emacs-based email agents such as VM-Mail and features a highly configurable interface, allowing easy set up of new translation pairs through Emacs' customization interface.