iTunes 3 has a pair of new Preferences I just love; both can be found in the Advanced pane of the Preferences window.

The first is called, "Keep iTunes Music folder organized." This nifty new option automatically creates folders for artists and albums in your iTunes Music folder when you import a song (via drag and drop, burning, or the File menu's Import command).

The second one is "Copy files to iTunes Music folder when adding to Library" and it makes the first one even better.

Here's how it works: My buddy emails me an MP3 file of a song ("You're My New Girl Tonight") his band ("Virgin") just recorded.

I download the enclosed MP3 file to my Desktop and double-click it. iTunes opens and the song begins to play.

Now, in the old days (version 1 and 2), I'd have to move the file to the iTunes Music folder myself if I wanted it to be added to my Library permanently. But with iTunes 3, two wonderful things happen behind the scenes and without any effort on my part:

1. iTunes creates the proper folder(s) for the song inside my iTunes Music folder. In this case it made a folder named "Virgin" (the artist's name), and since this song didn't have an album name associated with it, created a subfolder in the Virgin folder named "Unknown Album." Then, it copied the MP3 file from the desktop to the newly created (and properly-named) iTunes Music/Virgin/Unknown Album folder.

Pretty slick, eh? I'd say that's the tip for today but wait, there's more.

As much as I like this feature, there are times when I don't want it. Sometimes I just want to listen to an MP3 file, but I don't want it copied to my iTunes Music folder. Of course, I could open iTunes Preferences and uncheck the checkbox for "Copy files to iTunes Music folder when adding to Library." But that wouldn't be tip-like.

So here's the real tip: If you hold down Option when you drag a file onto iTunes main window, the choice you've made for "Copy files to iTunes Music folder when adding to Library" is temporarily reversed. So if the checkbox is checked, holding down Option will NOT copy files. Conversely, if the checkbox isn't checked, holding down Option will copy the file(s) to your iTunes Music folder.

P.S. In yesterday's tip I said I was, "putting the nearly-finishing touches on the 'iApps Bible' (or whatever it ends up being called)." Lead author Dennis Cohen wrote me early this morning to say that an official title has been selected by the publisher: "Macworld iTunes, iPhoto, iMovie, and iDVD Bible."

As Dennis said, it's obnoxiously long, isn't it? The book should be out before year-end.

To discuss this tip (or anything you like) in Dr. Mac's OSXFAQ Forum, click here:

Bob LeVitus is a leading authority on Mac OS and the author of 39 books, including Mac OS X For Dummies and The Little iTunes Book.