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THESE DAYS, IT'S EASIER TO MEET AN AMERICAN who has never heard of Judge Ito than one who hasn't been pitched a rebate credit card. For each dollar you charge on these cards, the issuer gives you anything from credits toward free airline tickets to cents off at your favorite store. About 100 million of the 387 million Visas and MasterCards that Americans carry are rebate cards, up from 40 million or so in 1992. And they keep coming: More rebate-card programs were introduced in the first 10 months of 1995 than in any previous full year, mostly by retailers such as Egghead Software, Toys R Us and Waldenbooks. In October, American Express even launched a program that gives cardholders rebates on goods and services from their choice of dozens of companies, including Marriott Hotels and Saks Fifth Avenue. But despite the plethora of cards, truly top deals are hard to find.

The vast majority of rebate cards work just like a regular Visa or MasterCard but are sponsored, or "branded," by both a bank and another company--say, an airline or an oil company. You use a rebate card to buy anything you could with a conventional credit card, but you also get rebates or discounts from the company that co-brands the card. The rebates come in the form of cash or, more commonly, product or service discounts. The more you charge, the bigger your rebate.

Problem is, the bennies you earn rarely make up for the cards' high interest rates, which usually hover one to two full percentage points above the average 18.2% on all credit cards and up to 11 points above the toll on the nation's lowest-rate cards, such as those listed at right below. "If you carry a balance each month," says Robert McKinley, president of RAM Research, a credit-card research firm in Frederick, Md., "you'll pay for your rebate several times over in interest." For example, if you charge $2,750 a year on the Discover cashback card (rate if you charge $1,000 or more per year: 17.6%) and carry a balance of $1,750--both average amounts, according to Bankcard Holders of America, a nonprofit consumer group in Salem, Va.--you'll earn a measly $13 cash rebate and pay $309 in interest.

The bottom line: None of these cards are a good deal unless you are a big spender and pay your bill in full each month. To get the most out of the card's rebate plan, you should charge everything, including big-ticket items like medical bills, a car or business expenses.

If you're willing to do that, then read on. Here's what to consider if:

YOU LOVE TO FLY You must charge a whopping $25,000 worth of stuff on most airlines' cards within three to five years in order to earn a free domestic flight. Cards that link up with the airline's frequent-flier program help you earn tickets faster. For example, with British Airways Visa ($50 annual fee; recent interest rate: 19.7%; 800-282-4273), each dollar you spend equals a mile, and you can add them to miles you accumulate from taking flights on British Airways and its affiliated airlines (Alaska Air, Horizon, Quantas and USAir).

Another good option: a card that gives you free or discounted tickets on more than one airline, such as CardMiles Visa or MasterCard ($38 after the first year; 12.6%; 800-842-4655). After you charge $5,000, you receive a coupon for $100 off any flight, domestic or international, on the airline of your choice. Four coupons, or $20,000, earns a free domestic trip on any airline.

YOU'RE A BIG TALKER Introduced in 1990, AT&T's Universal Visa or MasterCard ($20; 18.7%; 800-662-7759) is one of the best long-distance rebate cards around. Cardholders receive a 10% credit toward long-distance calls if they spend $10 to $25 a month on such calls charged to the card, and a 25% credit if they spend more than $25 a month. So $100 worth of calls gets you $25 back--a pretty good deal. One drawback: As of next year, you don't get a rebate from charging anything other than AT&T calls.

YOU PUT THE PEDAL TO THE METAL Of the 10 or so gasoline rebate cards, the Gulf MasterCard (no annual fee; 16.7% to 18.7% after the first year; 800-367-4853) stands out. It gives you a 4¢ rebate on future purchases of Gulf gas in return for every dollar of Gulf gas that you charge to the card (most competitors offer 3¢), plus a 1¢ rebate toward Gulf gas for every dollar you charge elsewhere. There's an annual cap of $350 on the rebate. If you spend a typical $750 a year on gas, your annual rebate from gas purchases alone is $30. You should put that number in perspective, though. Points out RAM Research's McKinley, "You can easily top a gas card rebate by buying gas across the street when it is cheaper by 10¢ a gallon."

YOU COVET NEW WHEELS Ford, General Motors and Volkswagen all offer rebate cards for which every dollar you charge earns 5¢ off the purchase or lease of one of their cars. Ford Visa or MasterCard (no annual fee; 19.2%; 800-374-7777) and Volks- wagen Visa (no annual fee; 17.7% after the first six months; 800-847-7378) offer the highest annual rebate ceiling: $700, for a total of $3,500 over five years. While that rebate is comparatively high, keep in mind that you must spend $14,000 a year to get the maximum.

YOU LOVE ONE STORE OR MANUFACTURER With retailers' and manufacturers' cards, the best rebates are generally reserved for goods that you charge from that store or manufacturer, and you must always apply the rebate to goods that are sold by the same outfit. One of the better cards of this type: Apple Computer Visa or MasterCard ($20 after the first year; 18.2%; 800-374-9999), which offers a generous rebate equal to 5% of all purchases made with the card if you spend more than $3,000 a year. If you spend less than that, you'll earn a 2.5% rebate (maximum: $500 a year).

YOU PREFER CASH Two of the dozen or so cashback cards are slightly better than the others. GE Rewards MasterCard (no annual fee; 17.9%; 800-677-1050) gives you 0.5% back for spending between $1 and $2,000 a year. A sliding scale hits a maximum of 2% for spending $6,001 to $10,000 a year--a higher percentage than most cards. But there's a rebate cap of $140 a year.

If you spend more than $14,000 a year, consider Cashbuilder Visa (no annual fee; 18.2% after the first year; 800-282-4273) instead. It offers a flat 1% rebate if you spend $200 or more each month, and there's no cap. You also get 10% off the interest you pay each month. So charge away.