Research scientist Andrew McAfee has discovered a 'feature' in Apple's iTunes software which could give the company cause for concern when it comes to staying on the right side of the law.
In a blog post, McAfee - who as far as we can tell has no connection to the security outfit of the same name - details how he was trying to put together an iTunes playlist to give to send to his mother as a gift, but was continually frustrated by alerts that the recipient already had some of the songs included in the list.
Because you don't need a registered account to create a gift playlist, McAfee suggests that it would be easy for anyone to guess an e-mail address and interrogate that person's music database, finding out exactly what music people were listening to.
Quite how that information could be used to anyone's detriment, apart from the obvious ridicule you will have to suffer if it turns out you are a 45-year-old Justin Bieber fan, is a bit beyond us. But their are some legal implications for Apple apart from the obvious erosion of privacy.
If you do manage to guess someone's Apple-registered e-mail address, and they happen to be logged into iTunes at the time, and they have publicly published details of their playlists, it is also possible to find out which videos they have downloaded or installed.
In America at least, the Video Privacy Protection Act protects a user's video rental history from prying eyes and could be brought to bear against Apple.
In the meantime, if you don't want people to know you have a full collection of the songs from Glee, don't publish your playlists.