Play sound in Emacs when mark is pushed. Interesting for discovering which commands push mark. (If not using OS X, insert appropriate sound file path.)

experimental.el

;; $ ls /System/Library/Sounds/
;; Basso.aiff     Bottle.aiff    Funk.aiff      Hero.aiff      Ping.aiff      Purr.aiff      Submarine.aiff
;; Blow.aiff      Frog.aiff      Glass.aiff     Morse.aiff     Pop.aiff       Sosumi.aiff    Tink.aiff

(defun camdez/push-mark--play-sound (&optional location nomsg activate)
  (play-sound-file "/System/Library/Sounds/Pop.aiff" 20))

(advice-add 'push-mark :after #'camdez/push-mark--play-sound)