I’ve been using an online music tracking service since March 2007. What it basically does is to monitor the music you listen to over a period of time. It has other uses too but this is one of the key things I use it for.
One of the features I like best is finding out which tracks or artists I’ve listen to most over a period of time. Last FM makes it easy to do this and track the last 7 days or even the past year or previous years and also provide a list of the overall most listened to.
You don’t have to tell the last FM site what music you are listening to but it tracks the music you are listening to via a small application known as an audio scrobbler. This works with iTunes, Windows Media Player and there are various other players out there which natively support scrobbling such as Songbird. When you finish listening to a track the scrobbler sends a message to Last FM site with the track name.
Obviously due to having to use the scrobbling app Last FM hasn’t managed to capture every single track I have listened to over the years, but mainly the ones from iTunes.
You can create your free account at http://www.lastfm.com
One other neat feature is you can make available your music listening habits to other websites to create fancy tag clouds one website which offers this is http://lastfm.dontdrinkandroot.net like the following
Most listened to albums

Music genres most listened to

Artists most listened to
