(function ($) {  
    var shift = {  
        "left": function (a) {  
            a.push(a.shift());  
        },  
        "right": function (a) {  
            a.unshift(a.pop());  
        }  
    };  
    $.marqueeTitle = function (options) {  
        var opts = $.extend({},  
        {  
            text: "",  
            dir: "left",  
            speed: 200  
        }, options),  
            t = (opts.text || document.title).split("");  
        if (!t) {  
            return;  
        }  
        t.push(" ");  
        setInterval(function () {  
            var f = shift[opts.dir];  
            if (f) {  
                f(t);  
                document.title = t.join("");  
            }  
        }, opts.speed);  
    };  
}(jQuery));