page 25) Balloon Surprise
Blow up a balloon and hold it tight to keep the air in . Now slightly open a door and on the outside put the balloon end between the door and frame. Carefully shut the door and the balloon should stay there blown up. Hide, and when an unsuspecting person opens the door the balloon will whizz off – giving them a fright.
From The Practical Jokers Handbook, by John Dinneen