From National Geographic's Confessions of a Backyard Submarine Builder.
Karl Stanley's first submarine, C-BUG (Controlled by Buoyancy Underwater Glider), is easily one of the most innovative personal submarines ever made. The lightweight craft operates primarily without the help of any motor, and even more impressive, it began as a ten-foot-long [three-meter-long] steel pipe, which Stanley began welding in his parents backyard 13 years ago. At the time, Stanley was a high school sophomore with no formal welding experience, let alone an engineering degree.
Sheesh. At 15 I wouldn't have been able to fix a flat bicycle tire, much less build a submarine.
Now Stanley's planning to build an underwater hotel. He says:
I'm going to have an underwater hotel, that's certain. It's going to ride up and down a cable from 800 to 1,000 feet [244 to 305 meters]. The capsule will be as simple to operate as an elevator.
The hotel will have a bed, bathroom, and I was even contemplating a Jacuzzi. I think that would be the ultimate luxury. You're hanging out in the Jacuzzi looking at a 4-foot [1.2-meter] window at 800 feet [244 meters], seeing sharks. The irony is pretty good, too.
Related Links:
Stanley Submersibles
Personal Submersibles Organization