Good subject Jim. I could come with a list but the most recent one was involving my thickness planer. I have it setting next to my table saw and I had a very bad habit of placing things on whichever one I am not working on. I placed my remote on the in feed while sawing and somehow it got bumped just out of sight. I then turned and ran the piece I was working on through and CRUNCH, requiring a new remote and turning the planer blades. Now I lean over and look before I start it.
Jack