array-unique.js

 Array.prototype.unique = function () {
    // make sure we have a unique string that is not a defined key in any object
    var uniqueString = "" + Math.random();
    for (var i = 0; i < this.length; i++) {
        if (typeof this[i] == "object" && this[i][uniqueString] != undefined) {
            uniqueString = "" + Math.random();
            i = -1;
            continue;
        }
    }
    
    var result = [];
    var accountedFor = {};
    for (var i = 0; i < this.length; i++) {
        var item = this[i];
        if (typeof item == "object") {
            if (!item[uniqueString]) {
                result.push(item);
                item[uniqueString] = true;
            }
        } else {
            var key = (typeof item) + item;
            if (!accountedFor[key]) {
                result.push(item);
                accountedFor[key] = true;
            }
        }
    }
    
    // Now remove the unique string from any objects we stuck it into
    for (var i = 0; i < this.length; i++) {
        var item = this[i];
        if (typeof item == "object") {
            delete item[uniqueString];
        }
    }
    return result;
}