$.fn.Ad=function(options){
var settings=$.extend({interval:1500},options);
var el=$(this);
el.append('<div class="bar"><a href=""></a></div><ul class="nav"></ul>');
var adNav=$('ul.nav',el);
var adTitle=$('.bar a',el);
var adPage=$('.page li',el);
var adPageCon=$('.page',el);
var adPageHeight=adPage.eq(0).height();
var numOfPage=0;
var indexAdShow=-1;
var countPage=adPage.length;
var adScrollId;
countPage--;
$('.page li',el).each(function(){
numOfPage++;
adNav.append('<li>'+numOfPage+'</li>');});
function toggleAdNav(){
if(0>=adPageHeight){
adPageHeight=adPage.eq(0).height()}
var adPageA=adPage.eq(indexAdShow).find('a');
adPageCon.stop();
adPageCon.animate({'top':'-'+indexAdShow*adPageHeight+'px'},{duration:'slow'});
adTitle.hide().attr('href',adPageA.attr('href')).text(adPageA.attr('title')).slideDown('slow');
adNav.find('li.current').removeClass('current');
adNav.find('li').eq(indexAdShow).addClass('current');}
$('.nav li',el).each(function(){
$(this).mouseover(function(){
$.stop();
indexAdShow=$(this).text();
indexAdShow--;
toggleAdNav();});
$(this).mouseout(function(){
$.start();});});
$.scrollAd=function(){
indexAdShow++;
if((indexAdShow)>countPage)indexAdShow=0;
toggleAdNav();};
$.start=function(){adScrollId=setInterval('$.scrollAd()',settings.interval);};
$.stop=function(){clearInterval(adScrollId);};
$('.page',el).mousemove(function(){$.stop();});
$('.page',el).mouseout(function(){
$.stop();$.start();});
$.start();};