Chase PerfectCard: 1% back on all purchases, 3% back on gas. Credited automatically to your next month's statement. Uncapped.

AT&T Universal card issued by Citibank, Citi Dividend: 1% back on all purchases, 5% back on purchases at grocery stores, gas stations and drug stores. Limit $300 in cash back per calendar year. Once you have accumulated at least $50 in cash back, you can call or request online a check for the current cash back amount.

Chase Cash Plus: 1% back on all purchases, 5% back on grocery store, gas and drug store purchases. Call or request online a cash back check in $50 increments. Limit $300/year.

American Express Costco TrueEarnings card: 1% back on all purchases (including costco purchases), 2% back on travel purchases (airfare, hotel, rental car), 3% cash back on restaurant purchases. At the end of the year (in Jan/Feb) you get a costco gift certificate which you can use for costco purchases, or you can bring it into costco and redeem it for cash.
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You can't always use it everywhere, but you get cash back on every single purchase. This is a better reward than something like airline miles because you can use cash back on anything; you can only use airline rewards for plane tickets.

My Discover has no annual fee. I don't know if this applies to all Discover cards, you'll have to do some investigating. I got mine while I was a student, so it may have been a special offer.

I used a Chase Mastercard once for a travel rewards program. They advertised the card heavily on the fact that it has no annual fee. Then, after I had used it for a little less than a year, they sent me a letter informing me that an annual fee would be introduced within a couple of months. I closed the account because I didn't want to deal with a company that was sneaky about annual fees like that. I didn't even care that I forfeited all my points when I closed the account because you essentially have to charge about $25,000 in order to get one free airline ticket.

With Discover, you get anywhere from 1% to 7% cashback on your purchases, depending on where you shop, so you can rack up a cashback bonus pretty quickly. They let you do it in increments of $20.00 cashback. Once you get to $20, you can claim your reward.
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