As I was walking near campus recently, I came across a curious sight: the front window of a home filled with an overhead projector. It was facing inward, not working as an old-fashioned Christmas projector for the yard. I have never seen such a scene.

Why was the projector in the window? My first guess is that the owner is a teacher or educator of some kind. Indeed, it wasn’t too long ago that these devices were used in numerous classrooms at all levels. From my elementary through college years, instructors frequently used them. While they were being phased out while I was in college, some of the older faculty still used them regularly. (Indeed, I recently showed a class a YouTube clip of physicist Geoffrey West making a presentation about cities at the Santa Fe Institute with the help of an overhead projector.) Even early in graduate school, I remember hearing advice that a presenter could have overheads as a backup should a Powerpoint fail to load. But, you would be hard-pressed to find one in a classroom on my campus today (though they and the film projectors only disappeared in the last few years). I have no idea what happened to them.

The overhead projector preceded bulky TVs on the way to the landfill – if you can find people willing to take them – and perhaps they will a return as a retro decorative item…