I'm always finding things out for the first time, pretty well every day, nearly every day. Latest might be relative, but craze, well for "banzai skydiving" I don't see a massive population following.

In terms of "new crazes" that's relative too, and often dependent on the technology. Parachute jumping wasn't popular during the 1700's for example because neither had been invented yet. There's been a lot of technology that's come up over the last two decades, that's the place to know where to look.

I've already mentioned and pointed to someone using a wing suit to land without a parachute. The wing suit is still undergoing developments, the first jet powered one since ~2010 the first electric one has only been around since 2020. This is diving without a parachute, or an enhanced function of it.

Then there is the 2012, still relative time, there is the Felix Baumgartner Jump From Space who set the World Record Supersonic Freefall. That means that he broke the speed of sound without being in an aircraft. Now with all due respect to the adrenalin rush one would obtain from jumping out of a plane without a parachute I think that between being offered the choice between the two, most hard core who know what they are effing talking about would go for the space jump... it's a no brainer.

Maybe from this list you can find one to your liking.

Smash and grab
Stolen Erection denial from June's Sex.
Looking at solar eclipses without sunglasses.
Disregarding safety concerns during a pandemic.
Taking a submarine down to the Titanic.
Parachuting from space (the video provided).
Free run
Captain Kirk's first space flight.
Tight wire crossing of Niagara Falls
Flyboarding
High slackfline
Drone whores: A real popular one sweeping Europe right now, people are dying by playing.
Base jumping...no plane required.

A few more of the classics here, relatively speaking.

https://www.youtube.com/watch?v=swaqst-SJTg

Now climbing might be as old as the hills but the heights are new. It's one thing to have a few moments of an adrenalin junkie rush but hard core know what the effing they are talking about hard core adrenalin junkies knows that with the proper technique you can edge....for hours.

And that's what draws the crowds...

Spiderman.

https://www.youtube.com/watch?v=jtK1IMDHRjA