You can buy a 20pk of Duracell Batteries for $12.99 at Staples and get a $12.99 rebate back! Now the rebate is only good in Staples stores so this isn’t a Free After Rebate item- but it is still a good deal as you can use the rebate to buy ink or paper or whatever you need!
The offer is limited to 2 per person per week through 12/26 or while supplies last. It is only good on AA or AAA batteries- you can get more details HERE.
You can use the .50 or $1 coupons to make this a better deal- but personally I would use the 20% off Office Depot coupon (they take competitor coupons) to save an extra $2.50. So pay $10.49 and get $12.99 back in store credit! (You can only use the coupon for one item.)