function retFalse(){return false;}
function clickNS(e) {
  if (document.layers || (document.getElementById && !document.all))
  { if (e.which==2 || e.which==3) { return false; } }
}

prvKey = 0;
nowKey = 0;
function keydown() {
  //out.line.value = "keycode = "+event.keyCode;
  if(navigator.appName == 'Netscape' && parseInt(navigator.appVersion)>4)
  {
    if(0 ==  event.keyCode){ event.keyCode = prvKey; }
    }
  //anti-refresh (f5 ignored)
  if (116 == event.keyCode){ event.keyCode=16; return false; }
  //process keypresses as usual
  prvKey = event.keyCode;
  return true;
}
document.onmouseup      = clickNS;
document.onkeydown      = keydown;
document.oncontextmenu  = retFalse;
document.onselectstart  = retFalse;
document.ondragstart    = retFalse;
document.onload         = function(){out.line.value = 'hello';}