What's with all those bottles or water Williams has got on the stage!
I think they are a represent of his act: every drop of water represents a joke he does and every bottle represents a funny joke he does. On the surface that looks like a lot of good jokes, but look closer and you'll see they are drowning in a sea of shit.

Another thing that comes to mind the the Macbeth quote, something about a tale told by an idiot, full of sound and fury but signifying nothing.