Pull String Fireworks
Not really fireworks, and not even classified as fireworks these fun little items go by the 
name, pull string fireworks, pulling tricks, booby traps and several other names they have come to be known by.
Pull String Fireworks often come in packages containing dozens. You may be surprised to learn how these multi-colored, small, cheap and noisy items work. Everyone has seen them in action: Give the string a tug, jump when it pops, then watch an unsuspecting friend jump back a few feet! Pull String Fireworks are packed with a tiny amount of gunpowder. The amounts are so minute that they aren’t even classified as fireworks, which is why they can be sold indiscriminately in grocery stores. More powerful firecrackers, such as M-80s and cherry bombs, are limited by federal law to 50 mg of gunpowder and under. A booby trap has much less than 1 mg of total powder weight.
Pulling tricks have been the media of many a prank over the years and a quick search of you tube reveals many, many ways people have used them to scare the pants off a friend. Whether tied to a doorknob, the toilet seat, or just sneaking up behind someone with them they can definitely cause someone to need a change of drawers! Commonly these are packaged in small boxes of 12 each and are fairly inexpensive considering the amount of fun you can have with them!
Here is a video of someone testing them. Pull String Fireworks Video
