I have succesfully implemented the Suckerfish dropdown menus in one of my current projects. Going to see how I can tweak it further now, and keep it functional under IE.
If you're interested. You can find it here:
http://keasu.com/beta/dchain/index2.php
Mouse-over the 'Bekijk uw opties' to view the dropdown menu.
No functions are currently working, because the database is not on this domain and not all the pages are done yet.