The funniest thing about the Bad Dog screensaver was that it was terrible at preventing burn-in as it left a substantial amount of the screen static while the dog ran around.
We had a utility called ‘*Mitnor,’ I believe, which had several options, but one of them was called ‘Centipede,’ in which you could enter a ‘time out’ message, which would travel around the screen.
*At least that’s what I think, as I can’t find anything about that company.
There was quick reference to the flying windows screen saver in the movie The Electric State that made me laugh but not the, much younger, people I was watching the movie with since they had never seen it or experienced the screen saver craze. During that time period I went through a number of different ones like one that was like a Cylon eye, and another that was the Matrix code.
//i\\
I still use one.
I had a Star Trek screensaver. It alternated between various screens: data readouts on planets from the series, tribbles multiplying and filling the screen, Tholian ships weaving a web across the screen, and Spock wandering across the screen, uttering various quotes.
Yup!
My family had Johnny Castaway when I was a teenager. Probably an illegal copy, because my parents were cheap like that.
At least Johnny Castaway put the island in a different spot each time, which I guess kinda sorta fulfilled its role as a screen saver. But it, too, had a lot of static imagery on the screen when it was running.
Those are around the lowrider bike scene but it’s a tiny niche. There was a popular revival during the chopper motorcycle tv show trend in the early 2000s. The one’s I’ve tried are really difficult to use.
My chrome is shining, bright like an icicle;
I ride around town on my lowrider bicycle.
-Beastie Boys
That is a good one. Way back in the very early 90s when I worked at a campus computer store the After Dark screensaver was probably our best selling software.
I think it was the prevalence of laptops. Much better for battery life to put the screen to sleep than to bounce around some toasters.
There are still old people who call their desktop wallpaper a screensaver. The same people who don’t know the difference between a forward slash and a backslash.
Hey! I resent that! I do so know the difference between the slashes. Just because I haven’t updated my computer vocabulary since 1986 doesn’t mean I’m completely ignorant. Now get off my LAN.
:: golf clap ::
The screensaver for Sun workstations was Conway’s Game of Life, starting with a somewhat random pattern and evolving until it repeated the process.
I particularly liked it because the Game of Life was our assembly language term project when I was in college, implemented on a PDP-1. The same one where Space Wars was developed.
We had that at work, and i enjoyed it.
My new Windows 11 laptop I bought in October has a screensaver. 
How about gyms? They’re obviously still around, but it seems (to me) maybe in the early 1980s to the early 1990s they were sprouting up everywhere before settling down to a more reasonable number.
Gyms/health clubs are still very much a thing, though Bally Total Fitness* – the chain which was behind a lot of that rapid growth – is now long gone. I regularly see ads for Planet Fitness, Lifetime Fitness, etc., so I’m not sure that they fit the spirit of this thread: “a more reasonable number” isn’t “went away.”
*- I had Bally Total Fitness as a client in the early 2000s. They were a ridiculous company, and were essentially in the business of selling financed three-year contracts to young stupid people; in order to make their business model work, they had to operate gyms/health clubs. It was widely believed that they primarily existed to launder money for the casino end of the company; I know that several of BTF’s executives from when I worked with them wound up in prison for fraud.
I guess you could define a subset: gyms that were essentially singles bars with exercise equipment. These dated (heh heh) to the early 1980s. Bally’s was the poster child, and was mostly sold to LA Fitness in 2011.
And they were around long before any of us were children, although as you note their proliferation into what seemed like every strip mall in the US was more recent. But I think they don’t meet the OP’s criterion of an actual new thing that wasn’t around when you were a child.
LOL.
It must really depend on where you live. Gyms are sprouting here like mushrooms. Must be 8 within a 2mi radius,. A new one is going in right around the corner from on of the bigger existing ones as we speak.
There was a period in the mid '00s where a lot of people had those walkie-talkie (push-to-talk-style) cell phones. They would make this very annoying chirping sound every time somebody stopped talking and released the talk button. Other people’s phone conversations are still very annoying, but at least we seem to be rid of that particular plague.