If you’d like to do a modern drop-down menuing system for your website but want to maintain compatibility as much as possible for people browsing with scripting turned off or older browsers you might want to take a look at the GRC menuing system which is entirely done in CSS without any help from Javascript or any other scripting language. Implemented largely by Steve Gibson with help from the GRC community the menuing system has been placed in the public domain so anyone can use it for free and allows tons of customization including at least two layers of menuing. Don’t take my word for it check it out yourself at the GRC script free menuing page.
Man, that stuff doesn’t even validate due to typos :S I think that is just lame.
Contrary to the above comment, the menu validates! The page itself however, does not. This has nothing to do with the menu itself… I stripped all the GRC related text and implemented only the menu. And it validates! Greetings!