飞来飞去的广告，当鼠标放上去时暂停，移开时又重新飞舞。
效果图：
Code<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>飘来飘去的广告</title>
</head>
<body>
<form id="form1" runat="server">
<div id="img" style="position:absolute;99px;height:50px;left:0px;top:0px">
<a href="http://lhking.cnblogs.com/" target="_blank"><img src="http://pic002.cnblogs.com/img/lhking/200902/2009021414542815.gif" alt="敬礼……" width="50px" height="50px" onmouseover="stop()" onmouseout="continuing()" /></a>
</div>
<script language="javascript" type="text/javascript">
var xPos=document.body.clientWidth/2;
var yPos=0;
var step=1;
var delay=60;
var height=0;
var Hoffset=0;
var Woffset=0;
var yon=0;
var xon=0;
var pause=true;
var internal;
function changePos()
{
width=document.body.clientWidth;
height=document.body.clientHeight;
Hoffset=img.offsetHeight;
Woffset=img.offsetWidth;
img.style.left=xPos+document.body.scrollLeft;
img.style.top=yPos+document.body.scrollTop;
if(yon)
{
yPos=yPos+step;
}
else
{
yPos=yPos-step;
}
if(yPos<0)
{
yon=1;
yPos=0;
}
if(yPos>=(height-Hoffset))
{
yon=0;
yPos=(height-Hoffset);
}
if(xon)
{
xPos=xPos+step;
}
else
{
xPos=xPos-step;
}
if(xPos<0)
{
xon=1;
xPos=0;
}
if(xPos>=(width-Woffset))
{
xon=0;
xPos=(width-Woffset);
}
}
function start()
{
img.visibility="visible";
interval=setInterval('changePos()',delay);
}
function continuing()
{
interval=setInterval('changePos()',delay);
}
function stop()
{
clearInterval(interval);
}
start();
</script>
</form>
</body>
</html>