globalオブジェクトを取得する ref: http://qiita.com/items/d249a2f2f13532748324

file0.txt

var global = this;

file1.txt

var global = (function(){return this})();

file3.txt

var e = eval, global = e("this");
//↓余計な変数を増やさない書き方
var global = ("global",eval)("this");

file4.txt

var global = new Function("return this")();

//newは省略可
var global = Function("return this")();

strictでは使えない

"use strict";
var global = (function(){return this})();
console.log(global); //undefined