I came across one of these a few years ago in a catalog which pushes expensive, outrageous gifts.
I never forgot it.
So when I discussed luxury item catalogs on the show I shared my infactuation with the Seabreacher. It is a sem-submersible watercraft which can be made to look like an Orca (Killer Whale), dolphin, shark, sailfish etc. The company has a YouTube channel and the clip I chose will give you a great overview of the craft.