There are many third party modules for Node. At the time of writing, August 2010, the master repository of modules is the wiki page.
This appendix is intended as a SMALL guide to new-comers to help them quickly find what are considered to be quality modules. It is not intended to be a complete list. There may be better more complete modules found elsewhere.
Module Installer: npm
HTTP Middleware: Connect
Web Framework: Express
Web Sockets: Socket.IO
HTML Parsing: HTML5
Serialization: msgpack
Scraping: Apricot
Debugger: ndb is a CLI debugger inspector is a web based tool.
Testing/TDD/BDD: vows, expresso, mjsunit.runner
Patches to this list are welcome.