It has been a fair bit of trial and error, but I have come out ahead. Here are the instructions on how to build your very own Altoid Tin Alcohol Stove. Also note that if you do something stupid with fire, you are the one that did something stupid. I am not liable. This instructable is meant to teach responsible people a useful skill.
Step 1: This Is What You Need:
Altoid tin - This is the main body of the stove. It is fairly difficult to proceed with no Altoid tin.
Metal Strips - These are used to make a pot stand that holds the pot above the flame to avoid smothering.
Cotton Balls - These absorb alcohol inside the tin, and displace air.
Alcohol - This is mostly just used for a rapid red-ox reaction to produce thermal energy from chemical energy.
Pliers - These are useful for prying the hinges of the tin apart to liberate the lid, and for un-liberating the lid again
Hammer - This helps if you decide to use nails to punch holes. I used a thumbtack for my first one, but I got tired of pushing with my thumb.
Thumbtack and/or Nails - These are great as far as making holes in things goes.
Measuring Implement - This helps for when you are making the metal strips, and you need to make sure they are not too large.
Sandpaper - This is used as an abrasive to clear the paint off the top and sides of your Altoid tin. This part is optional; if you do not do it the heat will.
Hacksaw - This is mostly unused. Tin snips > hacksaws. Unfortunately I have misplaced my snips...
Lighter - Lighters are typically used to set things on fire. I do not stray from that path in this 'ible.
Step 2: Liberate the Lid From the Tin
Do not bend the hinges too far, they could hinder the liberation of the lid if they are over-un-bent.
Also avoid warping the lid, as this will cause a worse seal with the body of the tin and make the alcohol pour flaming out the sides. It is not horrible, but it is not as good as a perfect seal.
Step 3: Poke Holes in the Lid
It might help to have more than one nail or thumbtack, as they get rather dull after clashing with so much metal.
I used a thumbtack for my first stove, but grew weary of pressing my sore thumb pad against a tack. So for the next two I made, I used a hammer, a finishing nail, and a block of scrap wood. This allowed me to punch the nail through the lid, into something that I was willing to tear up, and then pull the nail out and make another hole.
As far as hole patterns go, make sure that the holes are not too spread out, and that there are enough of them for good flow. If you have few holes spread sparsely across the lid, it will not heat the tin up enough to boil the alcohol in it and keep the stove going.
Make sure the holes are dense in the center. Do not put too many holes either, or it will turn into a raging inferno capable of burning rapidly through your fuel.
Step 4: Un-Liberate the Lid From the Tin
Basically, you must put the holes on the side of the lid back onto the hinges and bend the hinges back into the body. Undo what you did in the first step. Make sure the lid fits well and the hinge swings easily. If it does not, see if you can tweak the lip of the lid and the hinges to make sure it works properly.
Step 5: Add Cotton Balls
You do not have to pack a ton into the tin, but it helps to have the volume of the tin full of the cotton balls. The cotton balls are useful because they take up space where there would normally be air, and make an explosion of alcohol fumes less likely. Unfortunately, they also have residual alcohol in them after you finish with the stove, leading to wasted alcohol.
You may also replace cotton balls with fiberglass insulation; I have seen it done before. The advantage of insulation over cotton is that the insulation will not char like the cotton balls will.
Step 6: Pot Holder Strips
These are optional as you may have your own pot support, or because you may be using this stove for heat or for roasting things.
Take the two strips of metal (I used bits of Altoid tin lids, because I seriously have too many of them) and measure their width and length. They need to be long enough that they will support the pot over the whole stove, and narrow enough that they will hold the pot suitably close to the flames.
Cut slits half way through their width, so that they will fit together properly. This turns the two strips into an "X" shape that will hold up the pot.
Step 7: Mostly Done!
In order for the stove to work properly, you have to prime it. For an Altoid tin stove, this means I usually just set the cotton balls on fire for a few seconds, close the lid, pour alcohol on it, and light that. Then it should burn until it is out of fuel, heat, or oxygen. Just like most things.
Once the stove is lit, put the pot stand on it, and then the pot on the pot stand. Or, should you not need the pot stand, enjoy clean, hot flames.
Now you are done! I hope you have not set yourself on fire multiple times as I have, or that you have at least had fun doing it like I did. Questions, comments, and concerns may be listed down below the instructable in the "comment" section. If you have a suggestion, I will gladly hear it.
Thanks, and enjoy setting things on fire for the purpose of food consumption =D