What are some ideas for annoying pranks to pull on people?

First of all your never to old to play a prank but u have to be smart. now im not saying to go up to someone and tap on one side of the shoulder while ur standing on the other side laughing in their face because thats just plain stupid. first do the old classic invisible rope. get a buddy, then u and him get on a each side of the rode (not the highway, just a plain rode like in front of your house) wait for a car to come and then get low to the ground and start tugging on air like its a rope both of u not just one of u, the car will slow down and it will irritate the driver.one more is the old milk trick in a store . go to a store (has to be different each time never go to the same one) bring alot of clothes and keep it in the car . now walk in the store and camo your camera so no one will see it next go to the isle with a jug of milk and get next to a person and pretend to trip and fall then slam the milk on the floor while falling it will burst and spill every where. now after that pretend u cant get up and slip every where while kicking milk all over the person. it will irritate the hell out of the person