From time to time, I’ll randomly be followed down a hallway by a stranger (that coincidentally happens to be going where I’m going). When I turn a corner, I like to silently run ahead a few dozen feet, and then go back to my normal walking pace. Then, when the person following me rounds the same corner, they suddenly find themselves much further away from me than our paces would suggest.
I like to think this freaks them out a little.