The Steadicam, invented by Garrett Brown in 1975, revolutionized cinematography.

The SnorriCam, invented by Icelandic filmmakers Einar & Eiður Snorri (a/k/a the Snorri Bros) in the mid-'90s, offloaded the camera to the actor's body. A sort of hands-free selfie stick, it allows the filmmaker to fix the actor in the center of the frame as they move around. Everyone from Darren Aronofsky to Marvel Studios has used it.

Test footage from the '90s:

More recently the Snorri Bros invented a follow-up, the SnorriCam Sputnik:

This ingenious rig allows for footage of both the actor and the actor's POV, thanks to the pivot:

Here it is being used on the set of Bad Boys 4:

Confusing fun fact #1: Despite operating as the Snorri Bros, and despite having identical last names and similar first names, Einar & Eiður Snorri are actually not related.

Confusing fun fact #2: There are apparently two different ways to pronounce "Eiður." I can't reproduce either of them.