Polyfill for ES6 symbols for ES5 browsers. Originally written by Andrea Giammarchi. I just made it into a Component so I can use it easily.
$ component install anthonyshort/symbol
var Symbol = require('symbol');
var data = {};
var hidden = new Symbol();
data[hidden] = "Secret files";
console.log(data); // {}
console.log(data[hidden]); // "Secret files";
MIT