First, there was the Vans challenge, where Twitter users took off their sneakers and tossed them across the room, only to find they (almost always) landed the right way up.
Now there's the Crocs challenge, which is exactly the same... but with Crocs.
Participants are finding the shape of the Crocs means they too land face up every time.
If you want to get in on the action, simply grab your camera and start filming. Opt for Vans, Crocs, or perhaps even Converse to kick-start the next craze.
Social media trends aside, Crocs have been enjoying a high fashion comeback recently. Balenciaga thought they were worthy of a fashion moment when they released a pair of $400 platform Crocs last year.
None of the Crocs in the videos appear to be designer ones - perhaps they're just too precious to throw.