Proozy offers the Under Armour Men's HeatGear Armour Short-Sleeve Compression Shirt in several colors (Black pictured) for $24.99. Coupon code "PZY15" cuts it to $15. With free shipping, that's $2 under our August mention and the lowest price we could find by $5. It's available in select sizes from S to 3XL.
One grocery chain is likely to save you more money than any other.