OK, so maybe playing the accordion isn't unique, but I don't run into many accordion players these days :) This is me, aged 14 or 15, when I was not only taking lessons, but part of an accordion band! I have the accordion still, but it hasn't been out of its case in years.
@sugarmuser What has lasted for me is the ability to read music, which I'm very happy to have. I have an electronic keyboard that I fool around with from time to time.
@jacqbb I haven't in a long time, but could probably pick out a tune. The Marine's Hymn was one I knew by heart, and I can still play the right hand of that on my keyboard :)