
Popular mechanics brings us the Trilobis 65 a low cost (relatively) subsea semi-submersible home. They tell us:

At first glance, the Trilobis looks as if it would be more at home soaring into the sky than plying the waters of atolls, bays and maritime parks. Looking at a computer image of the bow conjures up visions of the flying saucers in 1950s science fiction films. The Trilobis’s blueprints, however, reveal a nautical heritage that reaches back to the humble dugout while simultaneously embracing 21st century technologies that include high-strength composites and nonpolluting hydrogen fuels.

The most distinctive feature of the Trilobis is its fully submerged first level, the observation bulb. Like the driving deck and day area above, it offers a commanding and unobstructed view of the sea. Only here, that view begins 10 ft. below the waterline. This is the smallest of the levels, just big enough for six chairs. Built to the same technical standards as tourist submarines, it is a thick glass enclosure that provides a 360° view. So that this area can be used when there’s no sunlight, the Trilobis has a ring of 200-watt spotlights, angled away from the observation bulb, to illuminate any sea life swimming directly in front of the viewers.
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