[рони]

Deff,
randomShuffle ок

Array.prototype.randomShuffle = function(c, b) {
    c = c || 0;
    b = ++b || this.length;
    var a = b - c;
    b = a - this.length;
    this.length = a;
    for (a = this.length - 1; 0 <= a && !(a < b); a--) {
        var d = Math.floor(Math.random() * a),
            e = void 0 === this[d] ? d + c : this[d];
        this[d] = void 0 === this[a] ? a + c : this[a];
        this[a] = e
    }
    this.reverse();
    this.length -= b;
    return this
};
alert(Array(5).randomShuffle())