Back in the days of film cameras, a few select Canon bodies had a very interesting feature: autofocus points controlled by your eye. The feature never made it over to the digital side of things, but that may change soon enough, with a new patent showing Canon researching the possibility of adding it to its mirrorless line of cameras.
Northlight Images recently found a new patent that improves upon a previous 2019 patent for eye-controlled autofocus by adding the ability to identify the specific user and subject memory. The feature, seen in the past on cameras like the EOS 3, followed the user's eye in the viewfinder, determining where in the frame they were looking and using that information to choose the closest autofocus point to the subject. It worked surprisingly well (and certainly, with three decades of improvements, would likely work even better today) and had many very devoted users. Of course, it was not for everyone, but one could simply turn it off if need be. I could certainly see it being useful for a wide variety of situations, such as for sports shooters or photojournalists covering very fast action that moves about the frame rather quickly. Like any patent, its existence does not mean it will eventually make it to a consumer product, but it sure would be neat to see!