Yoyo.com is currently offering a 15% off when you buy 2 or more LEGO sets (selected ones). Use coupon code LEGO15 or SUPERHEROLEGO. Free shipping on orders above $49. Does not stack with the 30% off one item (YOYO30) for first time customers. Thanks to forum member The-Daryl for the news.
*Some items like Hogwarts Castle ($123.99) are already reduced and stackable with the sale.