If you're in that 700-and-up class, don't be shy about using it to your advantage. When Varner's bank called to offer him a reduced interest rate for a balance transfer, the Atlanta-area resident thought the terms weren't quite to his liking.

Varner knew his credit score -- 749 -- made him a desirable customer. So he started negotiating.

"Not only did he give me a better rate, after that introductory rate expired, the original rate went down as well," says Varner.

Plunkett says savvy consumers with good credit, like Varner, can indeed wield their credit score to save money. Credit card companies are dealing with a lot of bad credit and may be very willing to negotiate to gain or retain a good customer.

"In this market for credit cards, you are in a good position to negotiate your rate. I could even say deflate your rate," Plunkett says. "But you have to have good credit. They're not going to do it if you've made late payments."

One caveat: If you do have a good credit score and want to shop it around for better deals, don't browse too long or too often.

Looking for a mortgage or an auto loan may cause multiple lenders to request your credit report, even though you're only looking for one loan. To compensate for this, the score counts multiple auto or mortgage inquiries in any 14-day period as just one inquiry. In addition, the score ignores all mortgage and auto inquiries made in the 30 days prior to scoring. However, this does not apply to credit card applications, which stay on your credit report for two years, but only affect your score for one year.