adidas via eBay takes an extra 20% off a selection of its adidas men's, women's, and kids' shoes and apparel. (The discount applies in-cart.) Plus, these orders receive free shipping. A couple of best bets, with prices after in-cart discount: adidas Women's Core 15 Training Pants for $15.99 (low by $11) adidas Men's N-5923 Shoes for $39.99 (pictured, low by $16)
These freebies are available to anyone with an internet connection — including those without an Amazon Prime membership.