Most popular, mid-to-high-range DSLRs eventually get their own waterproof diving cases, but this one is special. It's a Sea&Sea housing for a Canon 5D Mk II, and it lets you take videos like this:
This specific video was actually shot through a modded case, originally meant for the 5D Mk I, but the effect is the same.
Predictably, making HD fish screensavers with your DSLR isn't cheap: once you take care of import and shipping costs, it'll probably cost you nearly three grand—more than the body itself. [Akihabara]