People are even selling slime on Etsy. I did a search for slime on the site, and got over 17,000 results. I'm sure that not all of those are relevant, but a lot of them apparently are. Here's a clip of just part of the results.
People are adding glitter, sprinkles, figures and foam beads (and more). I'm not quite sure what the fascination with slime is (what does one do with slime?), but it's clearly a craze right now. If you want to make some yourself and see what it's all about, here's a video.
Here's another video by the same YouTuber that shows how to make slime without borax:
If you prefer written instructions, here's a link to an article that links to 17 variations on slime (including magnetic slime).
If I were babysitting or still teaching, I would totally do this. As it is, I'm just fascinated by the latest fad young people have latched onto.
Enjoy making slime or just watching the videos! (There are tons more videos online).