http://www.dynamicdrive.com/dynamicindex1/popupmenu.htm
http://www.dynamicdrive.com/dynamicindex1/flexdropdown.htm
http://www.dynamicdrive.com/dynamicindex1/ddsmoothmenu.htm

http://www.dynamicdrive.com/dynamicindex1/blmmenu/index.htm
  http://www.dynamicdrive.com/dynamicindex1/blmmenu/demo.htm