At Canon, buy one select Canon Photo Paper Pack and another four packs will be automatically added to your cart for free. (Eligible items are marked.) Plus, take an extra 50% off via coupon code "P150801". Shipping adds a flat $5 or get free shipping with orders of $200 or more. That beats our mention from last fall (which lacked the extra 50% off) and is the best such offer we've seen on photo paper from Canon.