I just accidentally used the Universal Control feature built into macOS Ventura. I had set up my work MacBook Pro next to the monitor for my personal Mac mini, where I used to keep my laptop when it was connected to this monitor. So I naturally just hauled the cursor beyond the side of the screen, and it magically kept going onto the laptop screen!
It took me several seconds to figure out that something special had happened and that my cursor had jumped from one machine to the other.
Something weird: how did it know which side of my monitor the laptop was on? It could guess by choosing the direction you try to move your cursor, exactly like I did, but it’s still absolutely delightful.