Banshee music player that comes with Ubuntu to play background music while I work. I must say that I find its user interface very slick and easy to use (I would even say it is an improvement on the RhythmBox player that they used before).
I don't look very closely at the user interface and so it was only recently that I spotted that they have an unheard view on your music library which shows the tracks in your library that you have never listened to. I was amazed to see that I had 715 tracks in this category (out of slightly more than 1,000 tracks in total). I know this does not really mean that I never listened to these tracks, it means that I haven't listened to them since I upgraded to Banshee a few months ago.
But it still tells me that my music listening is not as diverse as it should be. As a result I have set the player to play random selections from my unheard list for the last few days and I have really being enjoying discovering old favourites, although it can be a little strange to hear the music switch from Metallica, to Vivaldi and then move on to Horslips.