The American Express Centurion card, casually referred to as the "Black Card," is known as one of the most exclusive credit cards. Membership has its privileges, including concierge services, a rewards program and VIP treatment at hotels and resorts around the world.

The card is invite only, and offered exclusively to existing American Express customers. Accept and there's an initiation fee of $7,500, and annual fees of $2,500. Rumors of a spending minimum on the card were dismissed by an American Express spokesperson, who told CNNMoney: "It's how they spend, not how much."