http://stackoverflow.com/questions/14678721/

child.js

var Parent = require('./parent'),
    util = require('util');

var Child = function() {
  this.child = 'child';
};

util.inherits(Child, Parent);

Child.prototype.A = function() {
  console.log('Child#A');
};

module.exports = Child;

main.js

var Child = require('./child');
child = new Child();

child.A();
child.C();

parent.js

var Parent = function() {};

Parent.prototype = {
  C: function() {
    console.log('Parent#C');
  }
};

module.exports = Parent;

Running:

$ git clone https://gist.github.com/4704412.git && cd 4704412
$ node main.js