public function IsLoggedIn(){
      if(Member::currentUserId()){
         return true;
      }
   }   

   public function CurrentUser(){
      return Member::currentUser();      
   }

   <% if IsLoggedIn %>
      <li id="logged-in" class="mainmenu">
         <% control CurrentUser %>
            <span>You are logged in as </span>
            <strong>
               <% if FirstName && Surname %>
                  $FirstName $Surname
               <% else_if FirstName %>
                  $FirstName
               <% else %>
                  $Email
               <% end_if %>
            </strong>
            (<a href="Security/logout" id="LogoutLink">Logout</a>)
         <% end_control %>
      </li>
   <% else %>
      <li id="login" class="mainmenu"><a href="Security/login?BackURL=$Link">Login</a></li>
   <% end_if %>