We've all heard the stories from WW2 vets of using their steel helmets for numerous things, including to cook with. I thought I'd try my hand at it. Below is a helmet shell I just finished. This is a postwar shell that I stripped, refinished in WW2 style, attached chinstraps to, and then lightly aged.
This is the shell I'll be using as a cook pot, which was a fairly common practice during the war (though frowned upon by superiors since it altered the protective characteristics of the steel). Not to worry, I stripped the interior down to bare steel and seasoned it to make it safe to cook with. Obviously the guys out in the field didn't have a good way to remove the lead paint from the inside of the shell other than burning it out through multiple uses. Mmm, burnt paint flavor.
After seasoning I cooked an egg with it; makes for a great non-stick pan and the egg tasted great. The shell ain't so pretty anymore but it's far more useful this way.
So now I have a nice cook pot and some sad-sack noncom is running around without his steel shell.
After restoration, before seasoning.
Down to the bare steel.
Seasoning!
And cooking the egg.

Cooking with a WW2 M-1 helmet
Not so pretty anymore.