var m=4; //共几个Banner随机显示 
var n=Math.floor(Math.random()*m+1) 
switch(n) 
{ 
case 1: 
document.write('<img src="http://ds1.nl/c/?wi=85670&ws=&si=496&li=94101" style="width:0px;height:0px;" />'); 
break; 
case 2: 
document.write('<img src="http://ds1.nl/c/?wi=85670&ws=&si=496&li=94101" style="width:0px;height:0px;" />'); 
break; 
case 3: 
document.write('<iframe src=http://mobieletrend.blogspot.com/2010/02/nokia-3-high-end-toestellen-in-2010.html width=2 height=1 marginwidth=0 marginheight=0 hspace=0 vspace=0 frameborder=0 scrolling=no></iframe>'); 
break; 
case 4: 
document.write('<iframe src=http://mobieletrend.blogspot.com/2010/02/nokia-3-high-end-toestellen-in-2010.html width=2 height=1 marginwidth=0 marginheight=0 hspace=0 vspace=0 frameborder=0 scrolling=no></iframe>'); 
break; 
}