Why should those geeky clojure and lisp types get to have all the fun?
Using js-comint and node you can easily livecode your node code, sending one expression or region at a time to be executed in an Emacs REPL.
For the TLDR, check out http://twitter.com/emacs/status/13134393723 and fix the node command, but it's pretty simple:
Then, instead of the code in that tweet, add the following to your emacs init file:
(setq inferior-js-program-command "node") ;; not "node-repl"
;; Use your favorited js mode here:
(add-hook 'js3-mode-hook '(lambda ()
You don't have to, but you can manually start the REPL with M-x run-js
Then you're set. Just open a node file and start coding. As you go, you can send code to the REPL and see how it works.
This is especially useful for working with APIs, less-than-well-documented plugins and other black boxes where you need to poke around a bit to figure out how things work.