There’s a belief within the web standards community that Flash is part of a different world. While all approaches have limitations and drawbacks, Flash has been scorned to the point that many refuse to acknowledge its benefits.
There is a great ALA article that discusses CSS-based dropdown menus. It shows how to create "smart little menus that do the “DHTML” dropdown dance without sacrificing semantics, accessibility, or standards compliance". Since, the authors have writt