Established in 1850 in New York City, American Express Company was among the first and most successful express delivery businesses to arise during the rapid westward expansion of the United States. American Express makes money even if you do leave home without it. The company is one of the world's largest travel agencies, but it is equally as well known for its charge cards and revolving credit cards. And yes, the company still issues traveler's checks and publishes such magazines as Food & Wine and Travel & Leisure through its American Express Publishing unit, while its travel agency operations have more than 2,200 locations worldwide and its Travelers Cheque Group is the world's largest issuer of traveler's checks (it also issues gift cards). But the company's charge and credit cards are its bread and butter, and they've diversified along with the rest of the firm.