This guy milled through some PCB and other electronic components at 0.01mm depth passes and taking a picture after each pass and strung them into a video.
http://makezine.com/2016/03/02/watch-mesmerizing-dissection-multilayered-circuit-board/
http://makezine.com/2016/03/02/watch-mesmerizing-dissection-multilayered-circuit-board/