Get one of those two wheel RC robots.
Get pipe and two end caps. machine end cap threads off so they turn free like wheels.
Put robot controls, motors and battery inside pipe.
Leave lying someplace on sidewalk.
Bomb squad comes. Cordons off area. Approaches unknown pipe with their robot.
You roll the pipe robot a few feet away.
Bomb robot approaches again.
LMAO watching bomb robot chase pipe robot all over town.