This fantastically huge housing was put together by [Ed Sauer]. He put it together using TIG welded 6061 aluminum for the body and machined the port mount out of 7075 aluminum. The lens port is a commercial unit from a housing manufacturer along with a few manual controls. He wrote up the build in this pdf.
Underwater camera housings work great – but they are prone to humidity, dirt and dust problems if you open them more often than needed. In order to download the images off of his digital camera between dives, [Matt] decided to add a waterproof external USB port to his housing. He had an extra 5 pin strobe bulkhead installed by Ikelite (makers of excellent housings). Then he spliced on a mini-usb cable for the camera and spliced a standard USB end onto a strobe cable. During dives, the port is closed with an o-ring sealed cap.
Most people fear refilling their own ink cartridges. [Skipbreather] made his own CO2 scrubber refill for his rebreather. (Modern rebreathers are damn impressive.) The build is fairly straight forward, but requires some machining. I had to laugh when I found out that part of his build involved toilet seat hold down bolts.