Ending today, Groupon offers two Sony Stamina Plus AA or AAA Battery 72-Packs (144 batteries total) for $31.98. (Add two packs to your cart.) Coupon code "TRIPLE" cuts it to $30.38. With free shipping, that's $0.21 per battery, tied with our mention from three weeks ago, and lowest total price we've seen. (It's also the best deal we could find for this quantity of either battery type now by $26.)
You can alternatively buy one 72-pack for $14.39 after the above coupon, but shipping adds $3.99.