JavaScript - Lightweight, interpreted, object-oriented language with first-class functions
Chicken - A portable and efficient cross-platform Scheme implementation that compiles to C.
CrossBrowdy - Open-source JavaScript framework to create cross-platform and hybrid game engines, games, emulators, multimedia libraries and apps
Gambit - Cross-platform chess game.
Lua - Powerful, fast, lightweight, embeddable scripting language
CoffeeScript - Unfancy JavaScript