//menu
$(document).ready(function(){
  $('li.mainlevel').mousemove(function(){
  $(this).find('ul').slideDown();//you can give it a speed
	if(!ul.is(":animated"))
			ul.slideDown();
  });
  $('li.mainlevel').mouseleave(function(){
  $(this).find('ul').slideUp("fast");
  });
  
});