Updated June 25, 2013, with three new cases (Ballistic, Cascade Designs, and Lifeproof).
Waterproof smartphone cases used to be bulky, ungainly contraptions, but they've been trimming down lately.
That said, building a truly waterproof case is not easy (a waterproof case is defined as one that can be fully submerged underwater for at least 30 minutes). Often there are trade-offs in creating a waterproof design, the biggest of which usually involves access to the headphone jack on your phone. They also tend to be pricey, usually costing more than $50.
In boiling down the best of what's currently out there, I tried to provide a good mix of well-designed cases with a few more-affordable options that are a step up from a Ziplock bag.
Click on any image below to start the slideshow. (Products are listed in alphabetical order).