var origValue = [];
$('input.remember').each ( function (currentIndex)
{
       origValue.push ( $(this).val () );
       $(this).focus ( function ()
       {
               $(this).removeClass("unfocused");
               var defaultText = $(this).val();
               if ( $(this).val () == origValue [ currentIndex ] )
               {
                       $(this).val('');
               }

               $(this).blur(function()
               {
                       var userInput = $(this).val();
                       if (userInput == '')
                       {
                               $(this).val(defaultText);
                               $(this).addClass("unfocused");
                       }
               });
       });
});

A jQuery snippet to make form inputs show a help message which disappears on click (and comes back when the user enters nothing). Give your input the classes 'remember' to activate the snippet and (optionally) 'unfocused' as a CSS hook for changing the styling of the help message.