A4C offers the LifeProof Fre Waterproof Case iPhone 4 / 4s in White/Gray or Pink/Gray for $29.95. Coupon code "SLICK10" cuts it to $19.95. With free shipping, that's $15 under our December mention and the lowest total price we've seen. (It's also a current price low by $21.) It's designed to survive drops of up to 6.6 feet and it's fully submersible up to 6.6 feet.