If you buy new cars, Citibank has a "Driver's Edge" card where you earn 2% of your purchases towards a new automobile. They used to team up with Ford Motor Co. for 5% towards a new Ford product, but Ford discontinued their participation. Now, the 2% goes towards any brand of new vehicle.
Under the old Ford plan, we actually received about $2,100 off the purchase of a Mercury Villager. More recently, I got about $800 back on the purchase of a Nissan Altima. We charge almost everything we buy and pay the balance off every month.
My wife and I use the Delta Skymiles card (AMEX). The downside is you accumulate frequent flier miles towards Delta, the good news is you accumulate them quickly. ! mile per $ spent, except for home improvement stores, gas stations, grocery stores and a few other places where it is 2 miles for every dollar. They have a few promotions during the year where everything is double miles. We have taken 5 free first class round trip flights so far.....
Check out the MBNA World Rewards Platinum Card. I have it, my wife and I use it for everything. We paid for our entire wedding with the card and even redeemed points towards our honeymoon! I think it is the best travel card available because there is NO FEE, no blackouts and no airline restrictions. Also, since you are "buying" the tickets, you can get airline miles for the flights as well. The reward points are good for merchandise, gift cards, or travel -> 1 pt per $1 spent. The merchandise is "overpriced" so not worth it. Gift cards are at the rate of 13,000pts for $100 which is .77% back. At that rate you should get CASH instead at the rate of $40 per 5000 pts (.8%). Obviously, there are some cards that pay 1% back, but alot of places don't accept Discover, etc.
However, the travel is really good and where this card shines. For $25,000 spent, you get 25,000pts which equals roundtrip airfare in the continental US on any airline, no restrictions. HOWEVER, the ticket is only good for flights up to $400, over $400 and you can pay the difference. So basically, 25,000pts equals $400 towards airline tickets. So, in that sense its equal to 1.6% back.
Here is the breakdown... Airline coach-class reward levels: 25,000 points = one round-trip ticket to anywhere within the continental 48 states (maximum ticket value $400). 35,000 points = one round-trip ticket to Canada, Mexico, the Caribbean, Bermuda, Puerto Rico, the Bahamas, Alaska, or Hawaii (maximum ticket value $600). 50,000 points = one round-trip ticket to European destinations (maximum ticket value $800). 75,000 points = one round-trip ticket to South America, Asia, or Australia (maximum ticket value $1,200).
Car reward levels: 2,500 points = one-day car rental within the U.S. (maximum value $60) 15,000 points = seven-day car rental within the U.S. (maximum value $300)
Hotel reward levels: 5,000 points = one-night stay within the U.S. (room rate up to $80 per night). 10,000 points = one-night stay within the U.S. (room rate of $81-$160 per night). 15,000 points = one-night stay within the U.S. (room rate of $161-$240 per night).
I used to have an amex delta card just because delta was the only airline to get to where my parents lived, but the amex card had a $50 a year fee (although when cancelling they mysteriously offered me a version without a fee, but I can't find any information on that anywhere). Plus a ticket costs 15000-25000 points and you can't use them on holidays very much. I have recently switched to an amazon visa card. I thought about a car based card, but decided against it considering cars are long term purchases so all that time I'm saving up "points" I'm not really getting anything immediate from it. Which is why I'm really liking the amazon visa card. I've had it for about 3 months now and will be getting my first $25 off in a week or so. I figure I buy enough misc things on a monthly basis that the amazon card will actually suit me better than the others.
I don't know about the credit version, but Paypal's debit card gives ~1% interest for balances held in their accounts as if it were a money market account, and 1.5% cashback for all credit type payments. On the cashback, you don't have to wait for the end of the month before this is credited... it occurs immediately for every transaction.
I have the Disney Visa, which pays 1% back in Disney rewards, which can be used at the parks, cruiseline, stores, or online. For a Disney nut, it's a great card!
Plus, I use Upromise, which gets me back quite a bit of money toward my student loan. I've already earned $32.00 toward my loan, just by registering my cards and eating and buying from certain vendors.