When you buy a product that lets you down, you can either stew in bitterness or direct your frustration toward a productive end — whining to the company that wronged you. Zipping off a quick complaint email or phone call can often yield surprising results.

Nicole at Rainy Day Saver has had a run of bad luck with some products, and here’s the bounty she received by complaining:

Coca-Cola: She bought a six-pack and found that one can was empty. An email to customer service yielded a coupon for a free sixer.

Hewlett-Packard: She bought a cartridge and found it wouldn’t work. After talking it over with tech support, she sent in the cartridge and received one in return that worked.

Comcast: When her service was disconnected twice, she called to complain and was offered half off her next bill.

Be Your Own Consumer Advocate [Rainy Day Saver]

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