From another overlooked corner of the "World" comes the lockout tank at the Seas pavilion. I would love to try this sometime but I get the feeling that really isn't going to happen.
This reminds me of the good old days before Nemo stuck his tail into the seas. Back then the theming at the seas was top notch. They really tried to convince you that you were going far below the ocean surface.
You can see the video here.