Update: Use KMART10PSAVINGS for 10% off over $75 (if you plan on spending more than $45). Thanks melsig.
From December 9-15, Kmart United States will be offering a BOGO 50% off ALL LEGO Monster Fighters, Lord of the Rings, Star Wars, Hero Factory and Duplo. Pretty good themes! Plus, you can also use coupon code KMARTMUST for an additional $5 off $45. As always, Kmart offers FREE shipping on orders above $49. If the item is not available online, you can also try store pickup. Thanks to Brickbuilder0937 for the heads up.