American Express Costco Credit card is free when you have a paid Costco membership.  The card comes with 3% for gasoline purchases (upto $3,000), 3% for restautants, 2% for travel and 1% for everything else.

In addition you get $25 statement credit with your first purchase made with Amex Costco card.  There is also 0% APR for purchases for your first 6 months.