I was watching a tech talk by Doug Crockford called JavaScript: The Good Parts and JavaScript has inside-out objects, who knew :)

var singleton = (function () {
    var privateVariable;
    function privateFunction(x) {
        ...privateVariable...
    }
    return {
        firstMethod: function (a, b) {
            ...privateVariable...
        },
        secondMethod: function (c) {
            ...privateFunction()...
        }
    };
}());
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