Use ThinkGeek coupon code GEMINIO
ThinkGeek.com has this pack of Minecraft Sheet Magnets on sale for $9.99 after instant savings. Amazon.com has them for $16.50.
Each comes with 80 1" colorful, classic magentic blocks. If you like Minecraft, you'll probably spend a lot more time with your refrigerator, arranging the blocks. Free shipping with the coupon code.