Lua is a programming language originally designed for extending applications, but also frequently used as a general-purpose, stand-alone language. It combines simple procedural syntax (similar to Pascal) with powerful data description constructs based on associative arrays and extensible semantics. It is dynamically typed, interpreted from bytecodes, and has automatic memory management, making it ideal for configuration, scripting, and rapid prototyping. It is implemented as a small library of C functions, written in ANSI C, and compiles unmodified in all known platforms. The implementation goals are simplicity, efficiency, portability, and low embedding cost. It has been used on games such as World of Warcraft, FarCry and Angry Birds, among others.
CGILua is a tool for developing dynamic HTML pages and manipulating input data from forms. It uses the interpreted language Lua for codifying its scripts. It has been on the road for almost 8 years now, being used in many Web products and sites. It is extensible through Lua libraries and dynamic loading of C/C++ libraries. Scripts can be written as Lua programs or HTML templates (HTML with Lua code embedded). Scripts are platform-independent.
Slate is a prototype-based object-oriented programming language based on Self, CLOS, and Smalltalk. Slate syntax is Smalltalk-80-based, rather than trying to be clever and complex. However, the language semantics, environment, and run-time design are all much more powerful than in traditional Smalltalk systems. The design goal is to bring together many excellent existing ideas into one system, and to provide an environment where design decisions in one area don't constrain others.
tinypy is a minimalist implementation of Python in 64k of code. It includes a parser and bytecode compiler written in python. tinypy runs on its own C-based virtual machine with garbage collection. It supports a fairly decent subset of Python, including classes with single inheritance, functions with variable or keyword arguments, strings, lists, dicts, numbers, modules, list comprehensions, exceptions with full traceback, some builtins, and several modules.