Zagerz offers the OtterBox Commuter Series Case for iPhone 5/5S in Black or Blue for $10.99 with free shipping. (Scroll down to see the deal.) That's $4 below last month's mention and the lowest total price we've seen. (It's a current price low by a buck.) This case features two layers of protection and access to all ports, buttons, and features.
Note: The adhesive screen protector that often comes with this case is not included.
Amazon offers the Belkin Grip Power 2,000mAh Battery Case for iPhone 5 in Blue (pictured), model no. F8W292ttC02, or Purple, model no. F8W292ttC03, for $69.27 with free shipping. (B&H Photo Video and Lgeoo via eBay charge pennies more for the Purple case.) That's the lowest total price we could find in either color by $7. It features a shock-resistant bumper, anti-glare camera ring, microUSB charging cable, and headphone adapter.
Mr. Elephant offers the Mota Slim Protective Case Case for iPhone 5/5S in six colors for $1.99. Coupon code "CYBERSALE20" cuts it to $1.59. With free shipping, that's the lowest total price we could find by $5. It features 2-layer protection and comes with a screen protector.
Vistaprint cuts 50% offcustom iPhone and Samsung Galaxy cases (click through "Samsung Galaxy Cases" on the left to view these cases), with prices starting at $14.99. That's the best discount we've seen on these cases from Vistaprint since April, when we saw prices as low as $9.99 for iPhone cases. Shipping starts at around $5. You can create cases for the iPhone 4/4S, iPhone 5/5S, Galaxy S3, and Galaxy S4.