AnkerDirect via Amazon offers Prime members its Anker Ultra-Thin Bluetooth Keyboard Case with Stand and Lithium Battery for iPad Air, model no. AK-98APIPADAIR-BTA, for $29.99. Coupon code "IPADAIR5" cuts it to $19.99. With free shipping, that's $60 off list price and the lowest total price we could find. (Non-Prime members can spend $35 or more to qualify for free shipping; otherwise, shipping adds $8.54.) It features an 800mAh lithium battery for 320 hours of use, built-in stand, and USB cable.