First things first, if you carry a balance on your credit card, then rewards program cards are not for you. The finances charges and/or fees you'll pay on the balance will far outweigh any benefits from the rewards program. If you carry a balance, look for a card with the lowest interest rate possible so you can pay off your debt. And don't be fooled by introductory 0% interest rates. Those jump up quickly after the introductory period is over. Also, many of the 0% introductory offers will jump up before the intro period is over if you miss a payment or make a late payment.

There are lots of rewards cards out there, so one way to compare them is to use Money Central's credit card comparison tool. I've never used it, but after taking a quick look at it, it looked pretty useful.

Which ever program you choose, be sure to make the most of it. I know that with the with my airline miles rewards credit card there are all sorts of partner deals & programs that give me additional miles. They range from linking the rewards program account to a Safeway club card, to a restaurant rewards program, to double and triple points for purchases from partners. All of those extra miles can really add up.

However, be sure to pay attention to see when or how your miles or points expire. With some airline mile programs, points/miles do expire. If you know you won't use them frequently, opt for a program that has points that do not expire, like some of the Diner's Club or American Express points programs.

According to a recent article on Frequent Flyer Credit Cards in the New York Times, two cards stand out above the rest. The American Express Blue Cash and the Pentagon Federal Credit Union's Visa Platinum Gas Cash Reward card. The name is a mouthful, but the card is worth it!

The American Express Blue Cash card is great for big spenders. In a given year, after you spend $6,500 on the card it gives you 5% back on purchases from gas stations, grocery stores, and drug stores, and 1.5% back on all other purchased. Prior to hitting the $6500 mark it gives you 1% on purchases from the 3 types of stores and 0.5% everywhere else. It also has no limit on the amount of cash you can earn in a year, which is fantastic. There is no annual fee.

The other card, the Pentagon Federal Credit Union’s Visa Platinum Gas Cash Reward is a great option if you shop places that don't take American Express, or if you don't spend enough to make the American Express Blue Card worth while. It gives you 5% back on gas purchases, 2% at grocery stores, and 1.25% anywhere else. The only hitch is that you have to meet their eligitability requirements, the main one of which is having someone in your family who works for the US Government. However, if you do not meet them, you can join the National Military Family Association for $20 which is less than the fee for many other cards.

Soon I'm going to be looking through my spending history to figure out which card makes the most sense for me.