My mom went to the hospital last year to get some blood work done, and I went with her. In the cafeteria, they had these aluminum coke bottles. It was kinda rip off, it was like $1.79 for about 6 ounces of Coke... Anyways, I had it sitting in my room for a bit before I was a stoner. Then I realized I could make a cool bong. I drilled a hole in the side at an angle, and that was the downstem hole. For the actual downstem, I got pen tube and cut it about 5" long. Then, I cut about ½" off one end at a slant. This just made it easier to insert into the bowl. The bowl is a 13mm socket. It was hard to get the pen in sturdy, but it's okay now since it was cut at an angle. So I jammed the pen in real hard and it holds up pretty good, the bowl won't come off unless you pull it, it's fine to carry and set down. Then I drilled another hole in the opposite side for the carb. Here is the finished product.
That's freaking cool. I need to find something like that since I'm too cheap to buy a bong at the moment.
There are lots of things you could use. Try "ZachsHighShow" on Youtube, he has some pretty good builds. Waterfall bongs are extremely easy to make too, try those.
Smoke cooled by water is going to vaporize thick aluminum? This only applies to cases where the flame is in direct contact with or very close to THIN aluminum, such as foil. This is why tin foil bowls are bad. Obviously this bottle is much thicker, and after the smoke is cooled by the water, it's not even hot.