InkGarden is offering their 6"x2" custom banners for only $6 (regularly $25). Shipping is $5.99, making it $11.99 total. There are a lot of design options perfect for themed parties and showers, and you can even upload a picture or logo. I think another great idea is to make a simple "Happy Birthday!" banner to reuse for each family member throughout the year.
Go here to design your banner, and use coupon code BANNER2012 at checkout.
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