Amazon offers Prime members the adidas Women's Duramo 7 Running Shoes
in six colors (Night Flash Purple/Silver/Yellow pictured) with prices starting at $23.30
with free shipping
. (Note that prices vary by color and size. Non-Prime members can spend $35 or more to qualify for free shipping; otherwise, shipping starts at around $5.48.) That puts these shoes as much as $13 under what you would pay buying directly from adidas. They're available in sizes 5 to 12.