As one of its daily deals, MidnightBox again offers this Duracell AA Coppertop Batteries 40-Pack
for shipping. That's $0.37 per battery, tied with our August mention, and the lowest total price we could find for this quantity now by $5. (For further comparison, we saw 32 Duracell AA batteries with 8 AAA batteries for the same price four days ago — since expired.) Deal ends October 16.