Squirrel (programming language) - Squirrel is a high level imperative, object-oriented programming language, designed to be a light-weight scripting language that fits in the size, memory bandwidth, and real-time requirements of applications like video games.
Chicken - A portable and efficient cross-platform Scheme implementation that compiles to C.
JavaScript - Lightweight, interpreted, object-oriented language with first-class functions
Lua - Powerful, fast, lightweight, embeddable scripting language
LIPS Scheme - Scheme based powerful lisp interpreter written in JavaScript
bacon.js - A small functional reactive programming lib for JavaScript.