Can you recall a fad that came and went during your lifetime? Did you participate in it? How long did it last? Why do you think it faded?

Pokémon Go is very popular now, but I have never taken part in this fad.  A fad is a trend that is usually short-lived.  When I was younger, there were many video game and card game fads, but I did not participate in any of them.  This is because my parents did not have much money when I was a kid, and when I was a teenager I had to work too hard to make my own money to spend it on things like that.  I had things that mattered more to me.  I was never much of a video game person.
One fad that I remember was the pet rock fad.  People actually paid for pet rocks! Often they would be decorated, and sometimes colorful hair would be glued to them, or clothes.  Faces would be drawn on them.  This is completely ridiculous.  It is the perfect example of how people will pay for anything when it is a fad.  People join in on fads just because they do not want to be left out.  The pet rock fad lasted a few months.   As soon as people move on to the next thing, the fad fades out.
While I never had a pet rock, I will admit that I did have a pet screw.  It was a screw in a little wooden box.  I had this pet screw ironically.  It was a joke about the pet rock fad.  I am not sure if that makes it better or worse!
https://sites.duke.edu/english390-5_01_s2013/2013/04/30/an-in-depth-look-at-fads/