From The Associated Press
The State Department’s new passport cards (left), which are wallet-sized identification cards designed to speed border crossings by U.S. citizens to Canada, Mexico and the Caribbean, are proving popular already.
More than 350,000 Americans have pre-ordered the passport cards, according to the State Department.

The card is not valid for any type of air travel. It can only be used for land and sea crossings between the U.S. and Canada, Mexico, Bermuda or the Caribbean.
Beginning next June, travelers will be required to present documents proving both citizenship and identity when entering the U.S. through a land or sea border. For Americans who drive to Canada or Mexico or cruise regularly to the Caribbean, but who do not expect to fly abroad, the passport card is a cheaper, smaller, more portable alternative to a conventional passport book.

It is the size of a credit card or driver’s license, and has a photo and identification information printed on it, like a driver’s license. It also contains a chip with a random number that allows border officials to instantly retrieve your data.
“When you come to the border, hold your card up to your window, and on the border patrol screen, up will pop your name, your picture, the fact that you are a U.S. citizen, and the number of your card. They’ll peek in to see if you’re the same person, and speed you on your way,” said Deputy Assistant Secretary of State for Passport Services Brenda Sprague.

Passport cards are good for 10 years and cost $45 ($35 for children under 16). Applications can be made at any passport-processing site. If you already have a passport but want the card anyway because of the convenient size or quick scanning, it’s only $20 and can be ordered by mail.
More than 7,600 cards have already been mailed out to customers who pre-ordered the cards. All existing orders are expected to be filled by Sept. 30. New applications will take about four weeks to process.
Click here to find out the differences between a passport and passport card.