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. Deal ends January 13. A couple of best bets, with prices after in-cart discount:

adidas Women's Trefoil Tights for $19.99 (low by $8)

adidas Men's EQT Support ADV Shoes for $47.99 (pictured, low by $29)