autoload.js

Object.prototype.autoload = function(type, filePath, includeAsType){
  var obj = undefined;
  if(includeAsType === undefined) includeAsType = true;

  this.__defineGetter__(type, function(){
    if(!obj){
      obj = require(filePath);
      if(includeAsType) obj = obj[type];
    }
    return obj;
  });
}

example.js

var sys = require('sys');
var paths = require('path');
require('./autoload');

var foo = {}

foo.autoload("MyObj", paths.join(__dirname, "myObj"));

sys.puts(foo.MyObj);

myObj.js

exports.MyObj = {
  hi : "there"
}