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5. Gift cards

About 7% of the amount spent on gift cards isn't redeemed each year, which means Americans are sitting on about $30 billion in unused gift cards, according to the gift card exchange site Plastic Jungle. Now that's a waste.

Why not just give cash? At least you'll know that will get spent, and you're not limiting the recipient's options. You're also not subjecting the recipient to the various fees that come with prepaid cards, which are often marketed as gift cards that can be used anywhere.

If you don't like the idea of giving cash, you should rethink giving a gift card, which is basically just plasticized cash. It really isn't any classier than the real green stuff.