Costco offers two Amex cards. One offers cash back with a rebate rate that depends on the total amount spent. The other option offers 3% on eating out, 2% on travel and 1% on everything else. You get a voucher for use at Costco (not hard to use!) but you can get cash back for it at Costco as well. I usually pair it with IDine to get miles and a cash rebate.