From 9to5Toys.com

HandHeldItems knocks up to 93% off select Apple iPhone 4 cases. Plus, take an extra 20% off via coupon code “20iphonecs”. Even better, receive a $1 HHI store credit with your purchase. In all, 1,169 items are discounted, several of which are at or near lowest-we’ve-seen prices. (Scroll down to see them all.)

A best bet after coupon is the Silicone Cassette Tape Case for Apple iPhone 4 (pictured) for $3.87. With free shipping, that’s the lowest total price we could find by $1, assuming you use the credit. This case protects your iPhone 4 from dust and scratches and features pre-cut volume and port openings.