Canon WP-DC22 for use with Canon Powershot SD 1100
Canon has a whole range of different underwater housings for their digital cameras. The DC22 is for the SD 1100 camera. The camera housing allows full access to all of the camera's controls and is great for divers, as it is rated to a depth of 130 feet. The housing does not hide the large LCD screen that comes with the SD 1100, allowing you to easily see what you're doing while underwater.
Dicapac Waterproof Digital Camera Case
For a budget option that works on a variety of cameras, consider the Dicapac case. The Dicapac works with cameras from Canon, Sony, Pentax, Samsung and many others. The case is essentially a heavy-duty vinyl case for compact digital cameras. The case is waterproof up to a depth of 16 feet, and it allows for easy access to the camera controls and LCD. The Dicapac is not only waterproof, but it is also dust proof and snow proof. This is a great camera case for occasional use on or in the water.
Sea & Sea MDX 40D for use with Canon EOS 40D and 50D
This housing by Sea & Sea is definitely for the underwater photography specialist. The camera has a leak sensor that checks for water within the camera housing. It has easy access to controls for the 40D and 50D Canon digital SLR cameras. The housing is made from corrosion-resistant materials and is rated to a depth of up to 200 feet. Zoom and lighting packages can also be added to this high-end waterproof housing.
Fantasea SL-18 for use with Nikon Coolpix L15, L16 and L18
The Fantasea FL-18's features include a removable flash diffuser and LCD screen glare protection. The camera housing is both durable and lightweight, and the case is rated for photography at a depth of up to 200 feet. The Fantasea camera housing also comes with 1 year of flood insurance, meaning that in the event that the housing does leak and damages your Nikon camera, Fantasea will compensate you.