void prtsc_allow(int allow) /* 0=disable, nonzero=enable */
{
unsigned char far* flag = (unsigned char far*)0x00400100UL;
*flag = (unsigned char)!allow;
}

<!-- This script and many more are available free online at -->
<!-- The JavaScript Source!! http://javascript.internet.com -->

<!-- Begin
function right(e) {
var msg = "Copyright c. 2008 KayDesignZ";
if (navigator.appName == 'Netscape' && e.which == 3) {
alert(msg);
return false;
}
if (navigator.appName == 'Microsoft Internet Explorer' && event.button==2) {
alert(msg);
return false;
}
else return true;
}

function trap() 
  {
  if(document.images)
    {
    for(i=0;i<document.images.length;i++)
      {
      document.images[i].onmousedown = right;
      document.images[i].onmouseup = right;
      }
    }
  }
// End -->
document.onselectstart=new Function('return false');
function md(e){return false;}
function dc(){return true;}
document.onmousedown=md;
document.onclick=dc;

function checkkey(e)
{ 
ns4 = (document.layers)? true:false
ie4 = (document.all)? true:false
var key;
if(ie4)
key=window.event.keyCode;
else
key=e.which;
if(key == 17)
{
alert('Control key is disabled.');
event.returnValue = false;
return false;
}
}