The Free Library of Philadelphia is now offering the entire Sony Music digital catalog as free digital downloads. Through the library's website, hundreds of thousands of songs can be downloaded as MP3 files, to be played, copied and transferred at the whim of the user.

For years, the Free Library's website has offered tracks for download, but the music tended to be things you might find in the bins at thrift stores: the soundtrack to "West Side Story" or something called "The Once and Future Harp."

A private company called Library Ideas, based in Virginia, has hammered out an unprecedented arrangement with the major music corporation to offer their catalog to library users. For an undisclosed fee, the Free Library quietly launched "Freegal" last month.

"We've always had some CDs you could download through another service that we offer, but the titles you could get were not popular," said Jennifer Wright, the Free Library's assistant chief of material management. "They tended towards the New Age, the classical. As soon as we had this opportunity to have current and popular music, we jumped on it."

Navigating the selections puts the hippest music follower to the test. For example, almost all the music by Paul Simon is available to download because last year he moved his solo catalog to Sony, where his work with Art Garfunkel is also held.

But Simon's new album, "So Beautiful or So What," is not available because it was released by Concord Music Group. The 1990s indie band Guided By Voices is not available because there were on Matador, except for a live album recorded in Austin, Texas, in 2004. That was released on New West Records, a subsidiary of Sony.

There's one more catch. Cardholders are limited to just three downloads a week. That means it would take two and a half months to download that Guided By Voices live album in its entirety.