I think this menu is spectacular!

My question is this:

By default, the menu drops down, or if there is not enough room it goes up, and if there's not enough room for either it is positioned at the top edge of the browser window.

I was wondering if it's possible to change the behavior so that the menu continues to go down by default, but if there's not enough room then it posistions at the bottom edge of the browser window instead. In other words, it never goes up.

Can someone help?