On a whim I added a stainless steel foil pouch to my last order for McMaster-Carr. They are used to protect metal parts during heat treating. The foil is only .002" thick but it is infinitely more robust than aluminum foil.

It has VERY sharp edges. I carefully folded over the foil on three sides with some pliers. There's not much you can do with the open end, so I would advise against trying to drink directly from it.

I used a needle to poke a small hole on each side of the open end to thread with some snare wire as a bail. The pouch I tried is 2.5"x5" and when puffed open, it holds just over 1/4 cup. A one of the wider sizes would probably be better, even if you cut it down to be shorter.

Here's a short video clip of the pouch in use: Ultimate PSK Water Boiling Container

As you can see, the edges are cool enough to hold within seconds of taking it out of the fire.

What do you think?