Tanga offers the refurbished 2.4-lb. Apple MacBook Air Intel Haswell Core i5 1.4GHz 11.6" LED-Backlit Laptop for $454.99 with free shipping. That's $21 under our March mention and the lowest price we could find for a refurb today by $84, although most sellers charge $550 or more. It features an Intel Core i5-4260U 1.4GHz Haswell dual-core processor, 11.6" 1366x768 (720p) LED-backlit LCD, 4GB RAM, 128GB SSD, 802.11ac wireless, Bluetooth 4.0, Thunderbolt, USB 3.0, and Mac OS X 10.11 (El Capitan).
Note: A 90-day warranty applies, but it's unclear who backs it. It may show some signs of wear, such as scratches or other surface imperfections.