The Citi ThankYou Network in my opinion is one of the better reward programs offered from a bank. The great thing about it is it's for many different cards, and you can get points from each card and it all goes into one account.
Plus there are many redemption options; you can choose to receive a check in the mail, gift certificates, airline tickets, discount on a hotel reservation, and more.
Citibank also gives you special discounts if you shop through their website and use one of their credit cards.
To see which cards are part of the Thank You Network.