Dave's Underwater Housing for a Canon Digital Elph Camera
This is the 3D model of the aluminum camera housing with the Canon Digital Elph Camera (green). The back lid has an integrated hinge and a flange for a rubber O ring. There is a Plexy glass window in the back and in the front. This is a picture of the housing after about 40 dives. The aluminum has a nice layer of anodizing on it from all the salt water. The knob was made from a "stainless steel" bolt. It was cheep steel because there is a bit of rust on it now; otherwise the housing hasn't failed yet. (knock on wood)  
This is a stress simulation of the housing body if it were 100 Feet under water. The deformation is exaggerated to show what happens. The result of the model shows that the structure has a 4x safety factor. In other words, the housing can go 4x deeper or 400 ft before it approaches the yield point of the aluminum. This is the view of the same model from the other side. The color spectrum shows the stress concentration.  

CLICK HERE for 3D Stress Analysis (you will need to hit the refresh button)
(An application will load, ZOOM and ROTATE the model or hit PLAY)

Machining the front housing on a Bridgport 3Axis CNC mill. Machining the back housing lid on the same mill.  
My camera in action, check out my SCUBA link for more pictures.