There's a strange substance making some savvy people a lot of money.
It's gooey and sticky and wobbles when you prod it. As most kids will tell you, you'll regret eating it, or getting it stuck in your hair.
It's slime. But not the Play-Doh or lurid green gunk you grew up with — the new generation of slime is colourful and glittery, and comes in all sorts of textures.
As Jihee Junn points out in her article on The Spinoff, if you want to see just how big the slime craze is, take a look at Google's top trending searches.
Occupying the first, third and fourth most popular search spots in the 'How to …?' category are various questions related to slime, outranking even the most widespread queries on basic democracy and weight loss.
Videos of well-manicured women playing with slime are garnering millions of views on social media, and recipes for all sort of colours and textures are being shared on forums.
YouTuber Karina Garcia makes up to US$200,000 ($271,300) a month thanks to her 5.7 million slime-obsessed subscribers and her DIY slime book deal. The 23-year-old managed to buy a six-bedroom home last year.
As to why it's become so popular, most explanations veer towards its ability to tap into people's love for tactility and fidgeting (which popularised one of 2017's most faddish toys) and the internet's obsession with mesmerising visuals and sensory sounds, as demonstrated is this Instagram video:
Savannah Scott touched on people's obsession with slime in an article on Vice.
She says the popularity of slime videos on social media started in Thailand, when teens began posting video tutorials on how to make the stuff by mixing water, food colouring, glue and borax powder (a chemical used to kill cockroaches). They then played with the goo, adding glitter and colours.
"The results are strangely euphoric to watch, and the best slime videos feature sounds and visuals that can trigger Autonomous Sensory Meridian Responses (ASMR), a tingling sensation that starts on the scalp and moves down the spine," she explains.
"Today, some of the more 'slime famous' accounts have followers in the hundreds of thousands."
For example, this video has been viewed 264,000 times.
"Kids as young as 13 sell their products through e-commerce websites like Etsy and Mercari, receiving dozens of daily orders and raking in hundreds of dollars a week. People's love of goo is helping young entrepreneurs across the world pay for gas, contact lenses and college tuition."
It's true that some people have started to make serious bank from their various slime-related work.
In the US, YouTuber Karina Garcia purchased a six-bedroom home in California last year.
In June last year, Karina estimated she was making up to US$200,000 ($271,300) a month.
Speaking to Cosmopolitan, she revealed she got started in the slime business after finding there was a lack of recipes online for making slime, which she used to play with as a kid.
"I got obsessed with slime, out of nowhere," she said. "There was only like, one recipe for a basic Gak [a slimy modelling compound] online. So I just decided to go with it."
After her sister, who has her own YouTube channel doing beauty tutorials, encouraged Karina to create her own account, she was off and running.
Within a year she was supporting her whole family, including her parents and her siblings, through her hobby.
This video of her testing out slimes has been viewed just shy of 19 million times.
13-year-old Theresa Nguyen, who mans the Instagram account @rad.slime is said to be raking in up to US$3000 ($3746) a month from selling homemade slime on Instagram:
Time reports that Theresa initially sold her homemade slime through Etsy but she's recently started her own website. Her Instagram posts drive people to her website, which she restocks every Saturday with new varieties of slime. She says she sells out within hours.
Closer to home, 11-year-old New Zealander Katharina Weischede has entered the slime selling game.
"Slime is one of my favourite things. It's really satisfying and it always makes me stress-free," says Weischede, who started her business Slime Princess (not to be confused with Adventure Time's own SP) late last year.
"I definitely think it's more fun than other toys and I like it even better than Hatchimals."
Weischede says she was inspired to start making her own slime by Oobleck, a substance similar to slime. "I experimented with millions of recipes but none of them really worked for me so I took bits and pieces of the recipes and made my own," she says.
"I started selling it at school the first month but there was no hope. But soon it became super popular and I had a lot of batches to make."
When her parents found out about the popularity of her slime, they offered to help their daughter's fledgling venture by printing stickers, business cards and even T-shirts for her, all of which are emblazoned with the Slime Princess logo which Weischede designed herself.