So basically you have a coworker that needs to be taught a
lesson. Your coworker loves stress toys. They have
practically taken over his or her desk in a neat, orderly
fashion.
Wobbly type stress toys feature a big smile and an egg
shape. When you bop them, they wobble around,
eventually
coming to a rest. But what if they never came
to a rest?
What if the wobbly stress toy has an internal vibrator or
motor, designed to make the toy continuously, but ever so
slightly, wobble back and forth? Your coworker would
subconsciously notice something is wrong, but wouldn't
quite be able to put their finger on it. Eventually they
would take a closer look, and see that the wobbles never
quite stopped, that the wobbles NEVER stopped.
Perhaps they would call you over to verify this unusual
event. "Take a close look at this wobbly toy- see it
moving?"
And you would take a close look, and slowly stare into your
coworker's fearful eyes, and reply, "No." Then casually
resume your work duties.
The cognitive dissonance from the gas-lighting combined
with the soothing smile on the stress toy would culminate
into a maelstrom of stress.