Chicken is a Scheme compiler that translates most of R5RS Scheme into relatively portable C. It supports fully general tail-call recursion, first-class continuations, and has a very flexible and efficient interface to C and C++. Chicken implements several extensions to the Scheme language: lightweight threads, pattern matching macros, dynamic loading of compiled code, and various object-oriented paradigms, such as TinyCLOS, and others. The library system includes hundreds of convenient modules for practical use.
Eleven is a programming language for creating robust, scalable Web applications quickly and easily. It offers a 20x programmer productivity increase over traditional server programming languages like ASP, PHP, and JSP by automating state management and taking control of the application's look and feel. From high-level source code with a simple, C-like syntax, the compiler generates complete, ready-to-run implementations in PHP or mod_perl. Applications maintain their state in a relational database and are inherently fault-tolerant, secure, and scalable.
Halyard is a scriptable multimedia engine with support for video, audio, graphics, and user interaction. It currently runs on Windows, and has a preliminary Macintosh port. It is based on PLT Scheme, wxWidgets, and the Quake 2 Engine. It includes a rudimentary IDE based on Scintilla.
Kipt (Kizome's ISA Piercing Tool) is an HTTP proxy server and proxying name server with the ability to forward requests to other HTTP proxies or to get the documents directly from hosts. It can go through MS ISA Server or MS Proxy doing NTLM authentication. If you're stuck behind a restrictive firewall or proxy with at least one port open for outgoing connections and you have access to a machine outside, you can have nearly full Internet access by using this proxy and the socksify program from dante.
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.
MzVim is the Vim editor with an embedded MzScheme interpreter. MzScheme is a lightweight, embeddable, scripting-friendly PLT Scheme implementation. It provides full access to Vim commands and registers, and to VimL built-in variables and functions, so there is no need to execute Vim statements in string literal form. It also features OS-independent threads and an event-handling mechanism which allows Scheme to be used for autocommands, keyboard mappings, and menus.