Pure CSS2 Drop-down Menus. Drop-down menus without JavaScript? Enterprising designers like Stuart Robertson and Eric Meyer have created standards-based pull-down menus using the :hover pseudo-class to display other elements. By Andy King. 0529 [WebReference News]
Unfortunately all of these proof of concept menus do not support IE completely because of the sparse :hover class support. I still find www.gazingus.org use of a little javascript and css to be a more pragmatic approach.