FuncTools - Functional goodies for MooTools.
Interlude - ES5 JavaScript with Haskell inspired enhancements
prelude.ls - is a JavaScript functional programming library. It is the recommended base library for, and is written in, LiveScript. It is based in part off of Haskell's Prelude module.
daonode functional logic solver with built in parser
Introduction to Functional Programming in JavaScript - Presentation slides.