MIT Photonic Bands (MPB) is a free program to compute the band structures (dispersion relations) and electromagnetic modes of periodic dielectric structures, and is applicable to photonic crystals (photonic band-gap materials), optical waveguides, and a wide range of other optical problems. Its features include: fully-vectorial 3D computations, a flexible user interface based upon the GNU Guile scripting language, output in HDF format, and iterative, targeted eigensolver methods to address very large problems by solving for only a few states near a specified frequency. It runs on both serial machines and parallel machines with MPI.
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.
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.
Petite Chez Scheme is a freely distributable interpreted version of Chez Scheme, a high-performance implementation of ANSI Scheme with numerous extensions. Petite Chez Scheme may be used as a run-time environment for compiled Chez Scheme applications or as a stand-alone Scheme system. With the exception that the compiler is not present, Petite Chez Scheme is completely compatible with Chez Scheme.