Add a wireless adaptor, this will create a phantom experience to the user….
Wireless mice are handy things, but they’re full of prank potential. Wait until nobody’s looking and install a wireless mouse adaptor on your target’s computer, but leave their existing mouse connected.
Windows will accept input from both devices, so wait until your victim’s doing something fiddly and then send their mouse pointer on an adventure. If you only do it occasionally, this prank can go undetected for days
remember to quickly remove the evidence when they call for support