[Toadling]

Yeah, because the menu bar is always visible, one app must always be front-most. So if everything else is hidden, Mac OS X won't let you hide the last app.

Having said that, hiding OmniFocus seems to work fine here, as long as it's not the last app not hidden. I try to never hide the Finder so it can always be the front-most app when I hide other stuff.

-Dennis