Your media player should (hopefully) have a feature that shows your top "X" amount of played songs. I only picked 25 because that's what they give you on iTunes.
It's interesting to look at, for me. The first ten or so tracks are ones I listened to a lot last summer when I was in Kuwait, which is where I had a lot of downtime to listen to music. The last ten or so are ones that I've listened to this summer.