I just stumbled across this site which describes how to make a fire using a coke can and a chocolate bar. Basically you polish the bottom of the coke can using chocolate, which apparently acts as an abrasive, to make a parabolic mirror, and use it in a similar way that you would use a magnifying lens. I haven't tried it yet, but it's a neat idea, and I have no reason to doubt it would work. It's always good to learn new ways of making fire from improvised tools.

I like the mention of using toothpaste as a polishing agent. That's an old gunsmithing trick as well.

Been there, done that, it's an exercise in futility, you'd be better off practicing with a bow drill, or learning how to hand-spin cordage.

Troy

I dunno... I wouldn't want to rely on it as my only way to start a fire, but:

• I did polish the bottom to mirror smooth using toothpaste, my thumb and 40 minutes of my life I don't get back.
• I did manage to get dark newspaper to smoke nicely in bright sunlight using the mirrored end.
• I did manage to get a coal in a piece of cotton cloth rubbed with charcoal, using the mirrored end.
• I started quite a nice fire by transferring the coal to a handful of dried grass and blowing, gently.

It works, but in a fairly narrow range of conditions. It's neat to try at least once, if only just so you can say "Hey... watch this." (I have my polished Mt. Dew can on my desk right now. <img src="/images/graemlins/smile.gif" alt="" /> )