Digital telepathy. Some thoughts: (1) How would you implement this? If the devices were pre-configured to communicate with each other, like in a multi-monitor setup, it would be easy. Then, in addition to copy/paste and AirDrop, it would just be gesture recognition via the camera. (2) Furthermore, the devices would have to be pre-configured to communicate with each other in some way, because unless they were all logged into the same account, you could copy/paste random content onto someone else's computer just by pointing at the screen. (3) As long as both devices were logged into the same online account, all devices connected to that account would just poll the environment with their cameras until they caught the copy and paste gesture. If three or more logged-in devices with cameras were pointed at the user, you would have to consider edge cases, because the paste (or copy) gesture might be detected on multiple devices. (4) Then: Gesture-based computer interaction was really cool, but people could only do it with gorilla arms, so it was currently a relatively niche thing, only useful in video games and virtual reality. (5) However, with the rise of physical AI, it occurred to me that you should be able not only to talk to your robot companions, but also to gesture to them and make them do things. For example: point your finger at your robot dog and it will pick up a stick.