Big Bang Theory Holiday Ornaments are just .99 shipped at Think Geek. Use coupon code FREEREINDEER to get free shipping on any order. They have both the Bazinga! ornament above and a Soft Kitty ornament. I picked up both.
If you're spending more, you can use coupon code GALLEON to save 25% off $40 or more. Think Geek is a great place to shop for all the geeks in your life. I say that proudly!