I worked in an engineers some years ago.
We had a small room that housed a shadowgraph. As I went to enter the room one day, a workmate was exiting and he said page 17. As I got in there I found a lad's mag . I opened it and went to page 17. He had cum on a nude pic! I turned a few pages to a pic I fancied and did the same. This got banded about the workshop and within a week - there were no pages that didn't stick together....