gistfile1.js

var FOO = (function() {
   var a = "Hello";

   return {
      something:function(){
        alert(a);    // referenced via closure
      }
   };
})();

FOO.something();

gistfile2.js

var FOO = new (function() {
  this.a = "Hello";

  this.something = function() {
    alert(this.a);     // referenced via "this"
  }; 
})();

FOO.something();