Chutes
a.k.a. The Lung
This method is often referred to as chutes (shoots), or the lung, for what will be obvious reasons. It works on the same principles as buckets and the waterfall, except with a plastic bag instead of water.
Making Chutes
You'll need a 2L bottle, a plastic bag (without any tears), and some tape. Start by removing the bottom of the bottle. Now, take the plastic bag and tape it, airtight, around the bottom. This may take a couple of tries. To test, inhale through the top. If it works, the plastic bag should be sucked into the bottle (see 1 at the top).
For your bowl, take the cap off and cut it through so all you really have is a loop that screws on to your pop bottle. Take some tinfoil and push it through the loop so you have a bowl that goes into the bottle when you screw on the cap. Poke plenty of small holes into the tinfoil at the bottom. This is where your weed will be burnt.
When you're ready, either get a friend to hold the bottle, or hold it between your knees. Burn the weed and slowly pull the bag out of the bottle by the bottom of the bag. If you did this right, the suction should've brought smoke into the bottle (see 2 at the top).
For more smoke pull slower. If smoke is not going into the bottle, either you're plastic bag isn't on airtight, you've got a rip, or you're not pulling the bag out fast enough. This method is known to be harsh, so be careful your first time trying this. When you get the hang of it, you'll be able to take all the smoke out of the chute with one toke.