From now through 12/26, Staples is running a promotion on Duracell batteries: Buy one 20 count pack for $12.99 and get all your money back in the form of Staples Rewards. The limit on this deal is 2 per week! So you can get up to 40 FREE batteries every week. If you are shopping today (11/18), you can use this 10% off coupon for additional savings.
Thanks, Common Sense With Money!