An article in Sunday's Washington Post titled "Free Wheeling: Paris's New Bike System" shows tourists how to use Paris' Velib'. Make sure to bring your smart-chip Amex or Visa with you before you go.
"A major drawback for U.S. visitors is that you can sign up only with a smart-chip Visa card or an American Express card, a limitation that will leave a lot of Americans out in the cold. However, one card can be used to sign up several individuals. JCDecaux, the company running the system, says it hopes this problem will be resolved in the near future."
photo credit: The Washington Post