A variety of third-party utilities can display details about a track that’s currently playing in iTunes. But a reader has discovered a preference setting in Lion that allows song notifications to pop up over iTunes’ Dock icon. Here’s how to enable them.

First, quit iTunes if it’s running. Then open Terminal, type in the following command, and press Return:

defaults write com.apple.dock itunes-notifications -bool TRUE;killall Dock

Now relaunch iTunes, select a track, and press play. Down in the Dock, you’ll see a brief notification with the song’s name and artist (see ‘Song notification’). The notification will appear whenever the track changes, regardless of the app you’re currently using; it will then fade away on its own.

Enable a hidden setting to make iTunes pop up a little notification over its Dock icon whenever a new track starts.

If you decide you don’t like the notifications, you can get rid of them by issuing the same command, but replacing TRUE with FALSE.