QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.
SISC is an extensible Java-based interpreter of the algorithmic language Scheme. It uses modern interpretation techniques and handily outperforms all existing Java interpreters (often by more than an order of magnitude). In addition, SISC is a complete implementation of the language. The entire R5RS Scheme standard is supported. This includes a full number tower including complex number support and arbitrary precision integers and floating point numbers, proper tail recursion, hygienic macros, and full support for first-class continuations (not just the escaping continuations found in many other systems).
Industria is a collection of portable R6RS Scheme libraries for cryptography (AES, DES, Blowfish, HMAC, MD5, SHA-1, SHA-2, RSA, DSA, etc.), zip/gzip/zlib decompression, disassembly of amd64 machine code, Off-The-Record messaging, bytevector pack/unpack syntax, TLS connections via custom binary ports, and more.
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.
The Functional XML Parsing Framework is a package of low-to-high-level lexing and parsing procedures that can be combined to yield a SAX, DOM, validating parsers, or a parser intended for a particular document type. The procedures in the package can be used separately to tokenize or parse various pieces of XML documents. The package supports XML namespaces, character, internal, and external parsed entities, xml:space, attribute value normalization, processing instructions and CDATA sections. It is intended to be a framework, a set of "Lego blocks" you can use to build a parser that follows DOM, SAX, or another discipline, and performs validation to any degree. As an example of such parser construction, the package includes a semi-validating SXML parser. It converts XML to SXML, an instance of XML Infoset as S-expressions, an abstract syntax tree of an XML document. SXML can be queried (in a XPath style), transformed, and evaluated. The framework parses XML in a pure functional style, as folding over a text XML document considered a spread-out tree. The input port is treated as a linear, read-once parameter. The framework's code does not use assignments at all.
The Yehia Framework provides plugin management for C++ programs. You can conveniently incorporate both compiled and interpreted-language plugins into C++ programs. The use of several scripting languages in a single program is possible, and each scripting language runs either in the main thread of the program or in a separate thread.
Momoko is a generic, object-oriented, modular, extensible environment for creating multi-user environments. It is suitable for writing MUDs, servers, and community-based Web sites. It is written in pure Java and supports Java and Python as internal scripting languages. Momoko provides facilities for organizing objects into tree-based hierarchies, orthogonal persistence, a transparent distributed objects system, remote access to source code and user files via WebDAV, a telnet-enabled shell for manipulating the object database, and an integrated build process which can be triggered remotely.
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.