Amazon offers Prime members the OtterBox Armor Series Case for iPhone 5, model no. 77-25798, in Arctic Blue for $6.83 with free shipping. (Non-Prime members can spend $35 or more to qualify for free shipping; otherwise, shipping adds $6.29.) That's the lowest total price we could find by $10, although we saw it for $2 less in June. This waterproof case is purported to withstand a 10-foot drop, two tons of crushing force, and up to six feet of water for 30 minutes.

Note: This item ships in a damaged box and will probably be brand new with slight damage to the box.