Bed Bath & Beyond discounts a selection of curtains, with prices starting from $2.99. (Prices are as marked.) Shipping starts at $5.99 or get free shipping on orders of $49 or more. (In-store pickup may also be available for some items.) A couple of best bets:

• Argentina Pinch Pleat Window Curtain Panel from $18.99 + $6 s&h (pictured, at least $20 off)
• Isabella 84" Window Panel Pair for $41.99 + $8 s&h ($18 off)