Object Instances

module.js
```
module.exports = function () {
  return {
    name: 'default',
    set: function (name) {
      this.name = name;
    },
    ...
  };
}
```

main.js
```
var mod = require('./module.js');

var foo = new mod();
var bar = new mod();

foo.set('jesse');
console.log(foo.name);
// 'jesse'

console.log(bar.name);
// 'default'
```