Walmart offers Crazy Forts! 69 Piece Buildable Indoor/Outdoor Play Fort Playset for $41.40 (orig. $49.99) with free shipping.

Product Description:
"Crazy Forts are a unique, award winning, building and creative toy. Crazy Forts come with 69 child-safe toggles and rods that join together to build any play space from your child's imagination. Create a cave one day, an Igloo, Pirate Ship, or Castle the next ... put the pieces together in different configurations, cover with bed sheets and voila!, kids have a unique new play space every time! Crazy Fort is powered by a child's imagination. Each Crazy Fort Kit contains 25 geometrically precise balls and 44 sticks that connect to create a multitude of possible play structures. This kit comes with rods and balls, perfect for your little one."

Thanks Maggie