What in the world is wrong with this?

What in the world is wrong with this?

I made this today and it just doesn't want to work. I really have no idea why. Any help would be appreciated.

  2. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
  3. <html xmlns="http://www.w3.org/1999/xhtml">
  4.     <head>
  5.         <title>jQuery Popout Nav</title>
  6.         <script type="text/javascript" src="jquery-1.4.2.min.js"></script>
  7.         <script type="text/javascript">
  8.             $(function(){
  9.                 $('a').clicked(function() {
  10.                     $('#nav').toggle();
  11.                 });
  12.             });
  13.         </script>
  14.         <style>
  15.             #nav{
  16.                 background:red;
  17.                 height:300px;
  18.                 width:300px;
  19.             }
  20.         </style>
  21.     </head>
  22.     <body>
  23.         <div id="nav"></div>
  24.         <a href="#">Click me!</a>
  25.     </body>
  26. </html>
Thanks,
Keenan