We were setting up for a concert one time and I was helping the FOH engineer (sound guy) check all the instrument/mic lines. One of the instruments was a Moog synth. I started randomly playing it (I do not play piano or synth) so he could check it. After a couple of seconds he said something about me playing a song and I told him I had never heard of it. Apparently I had accidentally played the opening of a song he really liked.