function random_imglink(){
  var img=new Array()
  img[1]="images/main3.jpg"
  img[2]="images/main2.jpg"
  img[3]="images/main3.jpg"
  img[4]="images/main4.jpg"
  img[5]="images/main5.jpg"
  img[6]="images/main6.jpg"
  img[7]="images/main7.jpg"
  img[8]="images/main8.jpg"
  img[9]="images/main9.jpg"
  img[10]="images/main10.jpg"
  img[11]="images/main11.jpg"
  img[12]="images/main12.jpg"

  var ry=Math.floor(Math.random()*img.length)

  if (ry==0)
     ry=1
     document.write('<img src="'+img[ry]+'" border="0" style="float: left;" />')
}

  random_imglink()