function random_img(){
  var myimages=new Array()
  //specify random images below. You can have as many as you wish
  myimages[1]="images/banner1.jpg"
  myimages[2]="images/banner2.jpg"
  myimages[3]="images/banner3.jpg"
  myimages[4]="images/banner4.jpg"
  myimages[5]="images/banner5.jpg"
  myimages[6]="images/banner6.jpg"
  myimages[7]="images/banner_front.jpg"

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

  if (ry==0)
     ry=1
     document.write('<img src="'+myimages[ry]+'" border=0>')
}