NEW YORK (Reuters) - It may be about time to dig out that old library card. Hoping to draw back readers, libraries have vastly expanded their lists of digital books, music, and movies that can be downloaded by their patrons to a computer or MP3 player -- and it doesn't cost a cent, unlike, say, media from Apple Inc's iTunes or Amazon.com Inc.

In Phoenix, for instance, branches have banded together to create a digital library that currently has about 50,000 titles of e-books, audiobooks, music and videos that can be "checked out" from anywhere.

Once discovered, says Tom Gemberling, the electronic resources librarian for the Phoenix Public Library, the program often proves wildly popular.

Not long ago, Gemberling visited a local trailer park to speak about the program to 100 or so seniors -- who regularly travel the roads touring in their recreational vehicles.

"They were cheering and screaming by the end," he said. "They were so excited. They're RVers, so they can go anywhere on the road, find a computer, go into the Phoenix Public Library catalogue, download a book and play it while they drive down the highway."

Available in thousands of libraries across the country, the programs work like this: First you need a library card, access to the web, and some easily downloadable software -- the Adobe Digital Editions, the Mobipocket Reader or the OverDrive Media Console.

At that point, just browse around the library's website, select some titles, add them to a digital book bag and click the download button. If the title isn't available, it can be placed on hold for downloading later.

Depending on the library and title, the item remains on your computer for one to three weeks before disappearing, meaning you don't have to bother with returning a book, CD or DVD to the actual library.