Office Depot: 15% off USPS Shipping! October 2, 2010 by Mitchell Wischmann This post may contain a link to an affiliate. See my disclosure policy for more information. Wow! Office Depot has released a new coupon for 15% off shipping of any one USPS package! It’s very rare to find discounts on shipping, so I would definitely take advantage of this offer! Expires 10/15/10. Thanks, My Frugal Adventures!