How do i get a dropdown menu that when you mouse goes over the arrow it moves down or up

This (http://www.lissaexplains.com/fun.shtml) is a dropdown menu.

What do you mean by the "arrow moves down or up?" Have you seen this on a site somewhere? :)

http://www.dhtmlshock.com/scrollers/APScrollableArea/
http://simplythebest.net/info/javascript59.html

Something like that? (I know it's not a dropdown menu, but I'm trying here, heh)