Here is Ajax Login Module I wrote with YUI and an Open Source Template
1. The main page (index.php)

  1. <div id=‘loginDiv’>
  2.         <?php
  3.  
  4.         if((isset($_SESSION[‘userName’])))
  5.         {
  6.                 echo ‘<h4>Logged In<span> As</span></h4><div id=emailDiv>’.$_SESSION[‘userEmail’].‘</div><input type=’submit‘ value=’Logout‘ class=’button‘ onClick=’doLogout();‘/>’;
  7.         }
  8.         else
  9.         {
  10.                 echo ‘<h4>Login<span> Here</span></h4>Username<input type=’text‘ id=’userName‘ name=’userName‘ />Password<input type=’password‘ id=’userPassword‘ name=’userPassword‘/><input type=’submit‘ value=’Login‘ class=’button‘ onClick=’makeRequest();‘/>’;
  11.         }
  12.         ?>
  13.        
  14.         </div>
  15.  
  16.         <div>
  17.         <input type=‘hidden’ id=‘hEmail’ name=‘hEmail’ value=”/>
  18.         <h4><span>About</span> Me</h4>
  19.         <p>I work as a <strong>Project Manager</strong> in the LAMP domain, other interests include game programming, java, etc.
  20.         Mail me at birbal@techbirbal.com
  21.         </p>   
  22.         </div>
  23.  
  24. </div>
  25.  

Demo yuiLogin
demo user: birbal
demo pass: qwerty

Full Code Download yuiLogin