A bong is a different means of smoking it compared to the original joint or pipe.  It gives off more of a kick and is a definite must try for any weed smoker.  Below are a few bongs that you can make yourselves with blueprints and easy to follow instructions to help you along.

WHAT YOU'LL NEED:

A 1 Liter Soda bottle.
A Knife or razor
A bowl and stem
Clear silicone caulk or chewing gum (for the unprepared).
A drill with a drill bit a little wider than the stem. (you can use a knife, but the seal may not be great. A proper seal is key to this design!
Cut the Soda Bottle in half. Fit the Bottom end inside the top half. Take the cap and drill a hole in the top. Fit the stem through the cap and seal in place with caulk or chewing gum. Screw cap back into bottle.

HOW IT WORKS:

This bong works on suction not gravity. But if you haven't been going to classes much you might not know that! Start by compressing the two halves of the bottle together. Then load the bowl. NOTE: If you load the bowl during the compression stage the pot will fly out!!!! Light the dope and pull the two halves apart. This will cause the bottle to fill. NOW... remove the cap, put your mouth over the mouth of the bottle and compress (slide) the halves together. This should force a good amount of smoke into your lungs causing you to pass out on the floor of your dorm.
 

WHAT YOU'LL NEED:

A 1 Liter Soda bottle.
A Bucket (probably a gallon size is best)
Water- ice-water is preferred.
A Knife or razor
A bowl and stem
Clear silicone caulk or chewing gum (for the unprepared).
A drill with a drill bit a little wider than the stem. (you can use a knife, but the seal may not be great. A proper seal is key to this design!
Cut the Soda Bottle in half. Discard the Bottom end. Take the cap and drill a hole in the top. Fit the stem through the cap and seal in place with caulk or chewing gum. Screw cap back into bottle.

HOW IT WORKS:

This bong also works on suction and not gravity. Gravity and suction are not the same! Start by filling the bucket with water about 3/4 of the way up. Now push the top half down into the water. Then load the bowl. NOTE: If you load the bowl during the compression stage the pot will fly out!!! NOW- Light the dope and pull the top half up - but not OUT of the water. This will cause the bottle to fill with smoke. NOW... remove the cap, put your mouth over the mouth of the bottle and compress (push) the top half back down into the water. Smoke should rush into your lungs, the walls should melt, and you will likely become useless and believe that suction and gravity are the same.

WHAT YOU'LL NEED:

Strong Lungs
One of those big bottle from a Water Cooler (stolen preferably)
An VERY LONG aluminum or brass stem threaded on one end.
A big party bowl that matches the threads on the stem
A rubber stopper to put in the top with a hole to put the stem through.
A drillbit the width of the plastic tubing.
2 to 10 feet of clear tubing (get at a place that has stuff for aquariums like a pet store).
Clear silicone caulk.
Drill two holes to fit the clear tubing. Attach hoses. (NOTE: attach as many as you want!) Seal with caulk -let dry overnight. Stick stem through rubber stopper. Fill with water. Place stopper in top. Attach bowl. Destroy lungs!
 
 

WHAT YOU'LL NEED (this should be around the house):

A 12 oz. Plastic Soda bottle
A ballpoint Pen (Bic type- hollow tube)
A lot of Aluminum Foil
A needle (or toothpick)
Used Chewing Gum
Take the Soda bottle. Use pen to make hole in side a 1/3 up from the bottom. remove pen guts (so there is a hollow tube). Push into bottle and seal with chewing gum. Take aluminum foil and form bowl with a hollow stem at least 2 inches long (you want to make sure that doesn't melt the plastic pen tube - plastic fumes can kill you, or at least make you VERY sick. Use the pen to wrap the foil around - that will make sure you can pull air through it. Fill with water so that bottom of pen tube is below water. You now own the cheapest bong known to mankind! NOTE: Beware of lighting your hair on fire when you light this thing!
 

WHAT YOU'LL NEED:

A half a foot, and a foot long piece of clear plexiglass pipe, about 3 inches in diameter.
A base to put the cylinders on.
An aluminum or brass stem threaded on one end.
A bowl that matches the threads on the stem
A drill with a drill bit as big as the stem and a 1/4 inch drillbit (for making the carb hole)
A drillbit the width of the plastic tubing.
A piece of plastic tubing between a 1/4 and a 1/2 inch thick
A plastic cap to cover the first cylinder tightly (needs to form a seal)
Clear silicone caulk.
Attach hose through the top of the cap into the first cylinder (IMPORTANT: hose end should be ABOVE the water line). The other end of the hose, which goes in the second cylinder should be submerged under the water. Make sure the cap on the first cylinder forms a very tight seal!

HOW IT WORKS:

Load the first chamber boiling water and the second chamber with ice water.
Use normally, like a standard cylinder bong.
 

WHAT YOU'LL NEED:

An empty 2 liter soda bottle
3 to 5 feet of clear tubing (get at a place that has stuff for aquariums like a pet store).
A bowl attached to a long stem.
A knife or something similar to cut the holes in the plastic bottle (not so easy)
Clear silicone caulk.

HOW IT WORKS:

Assemble via the blueprint, then light up and draw through the hoses. Not as efficient as the expensive kind but it works.

Now you can act like turban-wearing Opium lord. A good project for a rainy afternoon.
 

WHAT YOU'LL NEED:

2 feet of clear plexiglass pipe, about 3 inches in diameter.
An aluminum or brass stem threaded on one end.
A bowl that matches the threads on the stem
A drill with a drill bit as big as the stem and a 1/4 inch drillbit (for making the carb hole)
Clear silicone caulk.

HOW IT WORKS:

I think you can figure it out.
 
 

WHAT YOU'LL NEED:

1 foot and 2 feet pieces of plexiglass pipe, about 3 inches in diameter. You will have to make a "Y" shape splitting off from the main pipe at a 45° angle. You will need plastic epoxy!
An aluminum or brass stem thread on one end (the thread to the valve has to attach to the stem).
A threaded brass valve that closes in half a turn.
A bowl that matches the threads on the valve.
A drill with a drill bit as big as the stem.
A cap from an aerosol can that will fit in the end of the short Y off the main pipe, just tight enough to close it off.
One foot of rope or bungee cord.
Silicone caulk

HOW IT WORKS:
Not quite as simple as a standard bong. The carburetor is the big pipe splitting off at 45°. This allows a LARGE amount of smoke to blast into your lungs VERY suddenly! The process is like this.

1. Light up.
2. Start smoking.
3. Close the valve (this cuts off all incoming air).
4. YANK the cord attached to the plastic aerosol top.
This causes a ton of smoke to go into your lungs instantly.
5. Pass out.