(function($) {
    $.fn.extend({
        slideshow: function(options) {
            var defaults = {
                height: 300,
                width: 500,
                theme: "",
                interval: 5000
            };
            var options = $.extend(defaults, options);

            var canvas = $(this);
            var listitems = canvas.children('li').get();
            var pos = 0;

            canvas.css("height", options.height + "px");
            canvas.css("width", options.width + "px");
            canvas.addClass(options.theme);
            canvas.html(listitems[pos]);

            setInterval(function(i) {
                canvas.html('').hide();
                pos++;
                if (pos > listitems.length - 1)
                    pos = 0;
                canvas.append(listitems[pos]).fadeIn();
            }, options.interval);

        }
    });
})(jQuery);