I can't believe a lot of you people have never done this. I use to do this over 10 years ago with my buddies, it's easy...I'll try and explain the best I can. This is what you will need:

-Weed
-Cut off, about halfway down the bottle of a small pop bottle, so you have the top half of the bottle
-Blowtorch
-2 kitchen knives, metal or course

Now, what you want to do is roll some small balls of weed/hash up. I mean small balls, if you've never hot knifed before, I suggest small balls about the size of a pellet, for a pellet gun. Now, once you have your balls all ready, you want to turn on the torch at at quite a high heat. Take your 2 knives, and place the TIPS of the knives over the hot flame. In about 1min or so, the tips of the knives should turn red hot. They have to be red hot in order for this to work. Once the tips are red hot, put the top half of the plastic bottle in your mouth, GENTLY pick up a ball using the red hot tip of the the 1 knife, it should just stick to the knife, if it doesn't, heat it up some more. Once the small ball of weed/hash is stuck to the one knife, it will start smoking, take the other hot knife in your hand and press the ball of weed in between the 2 knives, but before you press them together, carefully put the 2 pressed knives inside the bottom of the top half of the bottle, inhale, hold, and cough...repeat.

Understand now? I can't explain this any better than I did. It will send you into a coughing fit and go straight to your head. It's a great way to get ultimatly stoned.