Tanga offers the refurbished Apple MacBook Air Intel Haswell Core i5 1.4GHz 13.3" Laptop, for $499.99 with free shipping. That's $40 under last month's mention and the lowest price we could find now by $37. It features an Intel Core i5 1.4GHz dual-core processor, 13.3" 1440x900 LED-backlit LCD, 4GB RAM, 128GB SSD, 802.11ac wireless, Bluetooth 4.0, FaceTime camera, Thunderbolt, Mac OS X 10.9 Mavericks, and comes with a free case.

A 90-day warranty applies, although it's unclear who backs it.