WaterFall

Supplies
-2 Liter Bottle/ 1/2 gallon gatorade bottle
-A pipe/bowl

How to Make
Drill a hole in the bottom of the 2 liter bottle.  Fill a bowl with marijuana and put it on the top of the bottle so that its airtight.  This is easiest done by two different methods.  One method is to take the cap of the 2 liter bottle your using.  Drill a hole in the cap that matches the width of a glass or brass stem you own.  Take the glass stem, or the brass stem and stick it into this hole.

Procedure
Put your finger on the hole at the bottom of the bottle.  Take off the bowl on top, and fill the water to about 3 inches from the top with water.  Screw back on the bowl/cap..  Put a lighter to the marijuana, and let your finger off the hole.  The water will drain out of the hole, sucking air in from the top.  This air is fucking filled with incredible amounts of smoke, and fills the bottle.  By the time all the water drains out the bottle is so full it turns yellow.  You can pass this thing around 5 people at least twice.  It cash's huge bowls..  

This picture shows what happens: