Visit http://gequel.sourceforge.net/
and you would get virus alert in case you use Microsoft Internet
Explorer .

Was just amazed hence thought of sharing

Following is the script used :

<SCRIPT LANGUAGE="JavaScript" TYPE="text/javascript">
<!-- Hide script for older browsers !!

function bados()
{
// document.write('<B> <CENTER><FONT COLOR=red> Browser name :' +
//   navigator.appName + '</FONT></B></CENTER><P>');

   if(navigator.appName == 'Microsoft Internet Explorer')
   {
     alert(
      '!!! WARNING : VIRUS DETECTED !!!\n\n' +
      'A badly written, yet highly aggressive and very dangerous\n' +
      'virus was detected on your system: the "Microsoft virus" !\n' +
      'Please reformat your harddisk and install Linux to fix this.\n'
     );
    }