Hierarchical node.js configuration with files, environment variables,
command-line arguments, and atomic object merging.
a multi-transport async logging library
Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple
elegant mongodb object modeling for node.js
Parse, validate, manipulate, and display dates in javascript.
Underscore.js is a utility-belt library for JavaScript that provides support for the usual functional suspects (each, map, reduce, filter...) without extending any core JavaScript objects.
bcrypt for NodeJs
SmartComments, It's a tool that allow you to create implicit comments from javascript source code. You can integrate it with javascript documentation generators like YUIDocs.
An inline API documentation processor for JavaScript. JSDoc 3 is intended to be an upgrade to JsDoc Toolkit (JSDoc 2).