Taking conspicuous consumption to new...ahem..depths, U.S. Submarines manufactures submersible watercraft for the ridiculously wealthy. Check out the Phoenix 1000:
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For a cool 78 million clams, you could have your very own. Torpedoes not included (I think...).
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For a cool 78 million clams, you could have your very own. Torpedoes not included (I think...).