A long-running question on StackOverflow asks: can a website move your mouse cursor? The answer which is marked as ”accepted” unequivocally states ”it isn’t possible”. The most up-voted answer (with 195 upvotes) is even more dramatic:
Well, I like a good challenge. And guess what? It’s done. Click here to try it for yourself.
Edit: I originally released this as a fun little April’s Fools project. After the mouse moving demo turned out to be popular, I decided to create a mini-game around the mechanic: Ouija Online, a web horror experience.